## Problem
`BaseFamiliar.OnThink` drove its own movement (`WalkMobileRange` toward the master) while the familiar was also a controlled pet running `Obey()`. `Summon → SetControlMaster` issues `Come`; `DoOrderCome` converts it to `Stay` within two tiles and anchors `Home`; from then on `OnThink` walked toward the caster while `DoOrderStay` greedy-stepped back toward the stale post — the backtracking. Combat never approached anything: main only copied `Combatant` while already adjacent to the caster. `CurrentSpeed = 0.01` was a 10 ms think / 50 ms step sprint hack, and `RangeCheck` teleported the familiar to a spot eight tiles *from* the caster.
## Change
A dedicated `FamiliarAI : BaseAI` (registered through `ForcedAI`, like `CloneAI`) owns every familiar decision, for both the controlled (`Obey`) and uncontrolled (`Think`) dispatch:
1. **Lifecycle** — caster gone → drop pack, delete. Caster on another map → stand down and wait for `TeleportPets`.
2. **Herding** (Dark Tides) — stands down, then `CheckHerding()`. Outranks combat.
3. **Assist** — combat-capable familiars (dark wolf, vampire bat, horde minion) engage the caster's target; otherwise anything in a fight with the caster's side — attacked the caster or the familiar, or attacked by the caster (a pet's attack is credited to the caster) — that is still fighting the caster, the familiar, or one of the caster's pets. Leashed to `RangePerception` of the caster; dropped when the caster hides. Shadow wisp and death adder never fight (`AssistsMaster => false`, enforced at the `Combatant` setter so no path can hand them a target).
4. **Follow** — `MoveTo(master, 1)` through the centralized `ApproachTarget` (greedy step / persistent `PathFollower` / stall detection).
5. **Keep-up** — snap to a validated tile beside the caster (on the caster's floor) when outpaced on open ground beyond 10 tiles, or when `ApproachTarget` gave up; never while a detour is working.
**Command immunity** is expressed inside the order machinery rather than around it: `FamiliarAI.IssueOrder` does nothing and rests the order on `Come`, so `TeleportPets` keeps working and no system-issued `Attack` (retaliation on ML's stand-down rule) can strand the familiar. `StandsDownOnCommand => false` so the ML rule never mutes it.
**Visibility** mirrors the caster from the familiar's own state (a step reveals a hidden NPC in `Mobile.OnMove`; the old cache compared the caster's previous state), `RevealingAction` is suppressed while the caster is hidden, and becoming hidden drops Warmode so no swing gives the caster away.
**Speed** is a flat 0.1 (`ReduceSpeedWithDamage => false`).
### Engine-side (all `Projects/UOContent`)
- `ApproachTarget` records which exit it took in `BaseAI.LastApproach` (`ApproachOutcome`: Arrived / Waiting / DirectProgress / Routing / Blocked / GaveUp / InvalidGoal). Callers' booleans are unchanged; keep-up reads this instead of running a second scheduler. `MoveTo`'s arrival return now also clears the move intent, as `ApproachTarget`'s own arrival does.
- `MoveToPoint(goal, range = 1)`; `CheckHerding` passes 0. **Fixes a main regression from #2591:** herding stopped one tile short, never cleared `TargetLocation`, and left the creature pinned to the herding pace — affects the shepherd's crook and the Dark Tides scroll fetch for every herded creature, not just familiars.
- `ChangeAIType` reads `ForcedAI` once. It read it twice, and each `BaseAI` ctor activates its timer for a non-sector-gated creature, so a `ForcedAI` creature with `PlayerRangeSensitive => false` got an orphan AI ticking it.
## Tests
`FamiliarAITests` are timer-wheel driven (the real `AITimer` thinks and moves; `PetPacingTests` style) against live Trammel statics, gated on client map data: follow without backtracking, the five-way assist theory, leash, retaliation, aggressor fallback (caster's own `Combatant` expired; caster's pet in the fight), target dropped when it stops fighting, keep-up on open ground / not while routing / after give-up, hidden mirror across steps, herding priority with a visible fighting caster, stand-down when left behind, no stale move intent. `ApproachOutcomeTests`, `HerdingTests` (fails on main), `ForcedAITests` (fails on main) cover the engine-side pieces.
Against `origin/main` with the familiar tests dropped in: 16/16 fail, including the reported backtracking. On this branch: `UOContent.Tests` 1082 passed / 2 skipped, `Server.Tests` 891/891, solution builds with 0 warnings.
An uncontrolled creature with `Map == null` throws in `BaseAI.Deactivate()` when the condition reaches `Map.GetSector()`. A controlled creature with a null map avoids the exception but leaves its AI timer running.
Treat a null map like `Map.Internal` in the existing stop condition. This stops the timer without dereferencing the missing map and leaves the existing valid-map condition and return-home scheduling unchanged.
Addresses only the null-map `Deactivate()` item in #2627; the other audit items remain separate. No era-specific rules are changed.
## Summary
Pet orders lived in two files with nothing enforcing which phase owned what: `PetOrderHandlers.cs` ran one-shot handlers inside the `ControlOrder` setter and `PetOrders.cs` ran `DoOrderXxx` every AI tick from `Obey`. Friend/Unfriend refusals repeated their message every tick, Rename froze the pet, Drop on a dead pet never ended, the loyalty drain bypassed the release handler, and the command issuer leaked through a public field that only some handlers cleared (#2613 fixed the Release casualty of that split; this finishes the job).
Every order now lives in one place, `PetOrders.cs`, with two named phases:
- **Issue** — `BaseAI.IssueOrder(order, previous, issuer, resuming, interruptedTarget)` runs once, synchronously, from the new `BaseCreature.SetControlOrder` funnel. It may only set state and emit (message, sound, reveal) and returns the order to rest in. The funnel loops to a fixed point, so transient orders (Drop, Friend, Unfriend, Transfer, Release, Rename, Stop, Patrol) resolve before the setter returns and can never rest.
- **Tick** — `DoOrderXxx` runs from `Obey` for the six restable orders only (None, Come, Guard, Attack, Stay, Follow). Anything else that arrives there came from an old save and falls back to the standing order.
The issuer is a parameter: `BaseCreature.IssueOrder(order, issuer, target)` is the entry for player commands (speech, context menu, targeting), a raw `ControlOrder = x` assignment is a system-issued order, and nothing has to remember to clear anything. A resumed Follow restores the mobile the standing Follow was following, never a transient's target.
Because the funnel is synchronous it also carries the order being interrupted, so an administrative command can hand control back to what the pet was doing without storing anything per creature.
## Era behaviour, with sources
Two publishes govern most of the questions here, and the inherited code matched neither exactly.
[**Publish 16**](https://uo.com/wiki/ultima-online-wiki/technical/previous-publishes/2002-2/publish-16-part-2-4-23rd-july/) (23 July 2002) — *"The 'stop' command will stop a pet from guarding, following, and attacking."* Stop cancels the current attack and leaves the pet idle but still reactive. That is what this branch does whenever the stand-down policy below is off, in every era. (The same publish's *"Friends will only be able to issue movement commands to pets"* is the rule already enforced by `IsFriendOrder`.)
[**Publish 51**](https://uo.com/wiki/ultima-online-wiki/technical/previous-publishes/2008-2/publish-51-26th-march/) (26 March 2008) lists it per command:
> Follow: The pet should follow. It will not attack anything, even if it is attacked.
>
> Come: The pet should come. It will not attack anything, even if it is attacked.
>
> Stay: The pet will stay where it is currently, and will not attack anything, even if it is attacked.
>
> Stop: The pet will stop attacking. It will not attack anything, even if it is attacked, and may wander.
>
> Guard: The pet should guard as it does currently.
>
> Kill/Attack: The pet will attack its target as it does currently.
The inherited rule covered Follow and Stay only, so a pet told to come fought back, and it could not cover Stop at all: Stop resolves to None rather than resting, and None is exactly the state the publish describes. `BaseAI.IsStandDownOrder` now names the set — Follow, Come, Stay, None — and both halves of `AggressiveAction` read it.
## Configuration
`taming.petsStandDownOnCommand` (default `Core.ML`) controls the Publish 51 behaviour. The publish has no step of its own on the expansion ladder — it lands between ML and SA, and Kingdom Reborn was a client rather than an expansion — so it keeps riding ML as before, and the setting carries the rest: the behaviour is popular well outside its era, so a shard on AOS that wants it sets the key, and one that does not clears it. `BaseCreature.StandsDownOnCommand` is virtual for a creature that should differ.
## Bugs fixed along the way
- Friend/Unfriend refusal spam (every tick until the next command); Rename freezing the pet; Drop on a dead or non-`CanDrop` pet freezing the pet.
- Loyalty-zero release skipping the name clear and the summoned kill; a released pet keeping its `Friends` list and its previous owner's standing order.
- A transferred pet still answering to the previous owner's friends; transfer playing the idle sound twice.
- `BaseTalisman` summons issued `Friend` with no target (*looks confused* forever, or young-player spam); they follow their owner.
- Speech: single-pet commands lost their name gate after #2232 (a bare "come" moved every pet in range; "all stay" issued Stay twice); the speech cases passed a hardcoded `isOwner: true`, so a pet friend could say "`<name>` drop" and dump the pack, or issue Come/Guard.
- GM "`<name>` obey" was unreachable for a controlled pet; context-menu Release and speech Release disagreed about the control roll (resolved by removing it from both, below).
- Login derived the standing order from proximity even for a pet saved on Stay (zeroing its post), and only recorded the derived order without issuing it, so a pet saved mid-transient idled after a restart.
- `Friends` mutations never marked the creature dirty for delta saves.
- A resumed standing Follow was left without a target and cancelled itself to idle on the next think — the same defect as #2616, fixed here by `IssueFollow(resuming)` restoring the remembered target.
## Behaviour changes a shard maintainer will notice
- Every player command reveals its issuer, including context-menu commands from a hidden owner. This restores the blanket reveal (RunUO reveals in every order arm) minus its bug: it revealed the **control master**, so a friend's command popped the owner wherever they stood. Speech already reveals through `Mobile.OnSaid`, so the practical change is the context menu, target picks and the release gump.
- Resumed/chained orders are silent (no idle sound when falling back after Drop, Stop, a refused Friend, etc.).
- **Administrative commands no longer call the pet off.** Drop, Friend, Unfriend and Rename keep the pet's combat posture and hand control back to the order they interrupted, target and all; the standing order is the fallback only when the interrupted order cannot resume (a transient, or an attack whose target died, left or hid). Resuming an attack does not repeat its aggression or replay its bark.
- **Friend and Unfriend no longer rewrite the standing order.** Previously a success pointed the pet at the new friend and made Follow its standing order, so a pet left on Stay silently became a Follow with its anchor cleared. Friending grants a permission and nothing else; the friend has movement commands and can ask the pet to follow.
- **Releasing a pet no longer rolls the control chance**, on either path. A refused roll cost 3 loyalty, and loyalty reaching zero releases the pet anyway, so refusing only converted a deliberate release into an involuntary one minutes later. Both paths gate on `CanBeControlledBy` instead: if you can command it, you can dismiss it.
- **The pet distraction roll is gone.** A pet on Follow had a 10% chance per damage callback of dropping the order and attacking whoever hit it, issued without consulting anything, so it overrode the stand-down policy a few hits after the aggression path had correctly ignored it. Its era gate was guesswork by its own comment's admission and no publish describes it; `CanBeDistracted`, `CheckDistracted`, both call sites and the `Golem` override are deleted. Pre-ML shards lose the mechanic.
- **A pet's follow pace moved off the think clock.** The AOS sprint wrote a bespoke `CurrentSpeed = 0.1`, which fused both clocks — discarding any configured `ActiveMoveSpeed`/`PassiveMoveSpeed` — and pinned a following pet's AI at 10 Hz even while standing still. `BaseCreature.FollowMoveSpeed` (virtual, AOS 0.1) now caps the resolved step delay while the pet is closing on its master, the same way herding does: nothing stored, and a creature configured faster keeps its own pace.
- Transfer with an invalid target is a refusal (resumes) instead of forcing Stay; the transfer combat gate rests on the aggressor lists and `NextCombatTime`.
- Stop with no standing order anchors the idle where the pet stands (a vendor-bought pet no longer wanders off unbounded).
- The old "master must be alive" bails in the handlers are gone; stand-down and sounds run for orphaned pets too. RunUO gates only on the master being null or deleted, and a living friend commanding a dead owner's pet could not previously call it out of a fight.
- Login: a pet at None near its master is issued Follow silently; a saved Stay/Follow/Guard is adopted as is.
- GM "all obey" only reaches wild creatures; a controlled pet must be named.
- Death still issues Follow with the idle sound, as RunUO did.
## Tests
`PetOrderTests` grew from 16 to 63, plus 13 in a new `PetRetaliationTests` for the Publish 51 matrix and 13 in `PetPacingTests` for the clocks. Together they cover order resolution, reveal on every entry path, release parity (player vs drain, summoned), transfer/friend refusals and successes, stand-down and war-mode invariants, the interrupted-order resume, speech gating and permissions, GM obey, login derivation, the load probe, and the retaliation matrix across eras and both damage callbacks. Whole project green: 845 `UOContent.Tests`, 869 `Server.Tests`.
Fixes walk-up aggro latency (up to a full 10 s of obliviousness) and hardens the reacquire gate so no state can silence acquisition, while turning `AcquireOnApproach` into the reaction-time knob for future per-creature intelligence tuning.
### Why
`AcquireFocusMob` re-armed the 10 s `ReacquireDelay` **before** scanning, success or failure. A creature that scanned an empty room was blind for 10 s to a player walking up — walk-up aggro latency was uniform in 0..10 s. Waking from sector sleep stacked the AI timer's 0–3 s construction stagger on top. And `NextReacquireTime` is not serialized: on hosts whose tick counter starts negative (GCP pass-through), the 0 default blocked **all** acquisition shard-wide after a restart until the counter crossed zero.
### What
**Event-driven reaction — `AcquireOnApproachDelay` (the intelligence gradient)**
- The paragon `AcquireOnApproach` bool becomes a `TimeSpan` on every creature: an enemy moving inside `AcquireOnApproachRange` (10 for all creatures — on-screen reactive aggro; the periodic scan keeps the wide `RangePerception` sweep) *clamps* the next scan to at most the delay. Repeated steps cannot shorten it further — one scan per delay period, not per step or think.
- `Zero` (paragons) also prods the AI timer: the ranked scan engages within a wheel turn — the old snap, minus the special-cased engage path. The target now comes from the normal FightMode ranking instead of whichever mobile happened to move, and the `Combatant == null` guard stops re-engage spam.
- The 2 s default reads as "took a beat to notice you"; larger values are dumber; `ReacquireDelay` alone is the oblivious floor. Mover checks are the approach logic's `IsEnemy` + `CanBeHarmful` (so pets count and hidden movers are excluded via `CanSee`), with `IsEnemy` first to cheaply reject same-team wild creatures wandering past. The check rides the `OnMovement` callback every step already pays for — no polling added.
**Gate correctness**
- Every scan re-arms the full `ReacquireDelay`, success or failure (classic semantics; reaction time is the approach path, not the poll).
- Self-healing by construction: a deadline further out than `ReacquireDelay` is an illegal state and reads as open — no wedged or wrapped value can silence acquisition beyond one delay period.
- `NextReacquireTime` is seeded from a live tick on deserialize (the GCP negative-tick blackout).
**AI timer wake**
- Activation (sector wake, spawn, resurrection) starts within a 0–256 ms spread instead of the 0–3 s construction stagger, which read as lag.
- The stagger's real job — keeping same-speed cohorts out of lock-step (the RunUO town artifact) — is now a zero-mean ±period/8 jitter on each **idle** think, so phases random-walk apart within seconds and can never re-lock. Instrumentation showed why a one-shot spread can't do this job: the timer wheel fires within ±1 ms, so with 10 creatures on a 500 ms period some pair collides on nearly the same phase ~75% of the time (birthday paradox) and then steps in the same loop iteration *forever*. Jitter is scoped to passive speed: engaged cadence stays exact, since pursuit timing anchors to real step times.
**Debug**
- The `AcquireFocusMob` scan message no longer re-arms the shared 5 s debug cooldown, which swallowed every AI's "I have detected X" transition line.
**API change** for custom scripts: `AcquireOnApproach` (bool) → `AcquireOnApproachDelay` (TimeSpan). Documented in `content-patterns.md` § Target Acquisition, `runuo-migration-docs/09` + `11`, and the migration skill checklist.
### Tests
`AcquisitionTests`: both scan outcomes honor `ReacquireDelay`; a 60 s-wedged gate still acquires; enemy movement clamps the deadline (same-team wild movers and out-of-range movers ignored); repeated movement cannot shorten below the delay; `Zero` opens the gate and prods without a direct engage. Full suite: 755 UOContent green.
Stacked on #2594. Fixes jerky creature movement (lich / Fast-bucket melee chases) by choosing the client animation flag from the actual step pace instead of a caller-supplied `run` argument, and fixes three step-pacing defects in the move budget found while verifying it with paired server/client traces.
### Why
The `Direction.Running` bit does nothing for creatures server-side (`Mobile.OnMove` reads it only for the player throttle and stealth reveal). Its whole effect is on the client, which animates each step over a fixed time selected by that bit: walk 400 ms / run 200 ms on foot, 200 / 100 ms mounted. ClassicUO queues up to 5 steps and *drops* the sixth, so a creature stepping every 300 ms while flagged as walking backs the queue up until it snaps forward — the observed jerk.
The `run` argument never carried the one fact that matters (the step interval). RunUO passed `true` in combat / `false` for pets and gated it on `dist > 5`; #2271 flipped every combat site to `false`; pets passed `currentDistance > 2`. None of that is a coherent signal.
### What
**Pace-derived run flag**
- `BaseAI.ShouldRun()`: run iff the effective step delay (move clock + badly-hurt inflation) is shorter than `Movement.WalkFootDelay` / `WalkMountDelay` (mounted or flying) — with a continuity rule: an *isolated* step (taken after standing at least a walk interval) goes out as a walk, because the client renders each step alone and a lone run-flagged step is a 200 ms dart. Only a continuing cadence flags run; a true sprinter (pace under the run interpolation) always runs, since a walk-rendered first step would flood the client's 5-step queue. This reproduces RunUO's close-in feel (its `dist > 5` gate) from first principles.
- `DoMoveImpl` stamps the bit; it is the single place the flag is set.
- `run` removed from `MoveTo`, `WalkMobileRange`, `ApproachTarget`, `MoveToPoint`, `MoveToWithGroup`, `MoveToWithCollisionAvoidance`, the move intent, and `PathFollower.Follow`. All 35 call sites updated. **API change** for custom scripts — documented in the RunUO migration docs (`09-items-mobiles-creatures.md`, `11-api-reference.md`) and `content-patterns.md` § Creature Speeds.
**Move-budget pacing fixes** (each confirmed by UTC-aligned server/client step traces)
- A stall no longer banks catch-up steps: the budget's snap-to-now released up to three steps in ~300 ms when a creature resumed chasing after standing beside its target — rendered as a teleport.
- Debt accrual removed entirely: a step landing sub-period late (think-grid vs budget misalignment during reactive mirroring) kept the remainder and fired a follow-up ~100 ms later — a dart pair. `ConsumeMoveBudget` now paces every step from when it was actually taken; in continuous pursuit the move-wake lands within wheel resolution of the deadline, so the cost is single-digit-ms drift.
- Net effect: a creature can never step faster than its pace, verified across a full chase session (zero sub-pace steps; metronomic 350 ms cadence for a 0.3 s lich).
- Test fixture now runs `Movement.Configure()` (the walk delays were 0 in tests).
### Accepted trade-off
Animal (LOW group) bodies without a run animation slide on their stand frames when flagged as running. Most are slow enough to stay flagged as walking; the client-side fallback is in ClassicUO/ClassicUO#1930.
### Tests
`RunFlagTests`: foot thresholds (0.3 / 0.125 run; 0.4 / 0.45 / 1.05 walk), flying uses the mount threshold, badly-hurt inflation flips a 0.35 s creature back to walk, a real `DoMove` stamps the bit, isolated steps drop to walk (sprinters keep running), a stall restarts the cadence with no banked steps, and a late step earns no quicker follow-up. Full suite: 837 Server + 747 UOContent green.
Closes#2593. Closes#2595.
Two related pet-AI fixes: the post-#2591 pacing/wake regression (#2593), and the guard order silently converting to Attack during combat (#2595). Root-cause analyses are in the issues.
## #2593 — pets follow slowly; stale AITimer wakes
**Why pets slowed:**
- The per-step budget grew from **half a think interval** (`CurrentSpeed * 500`) to the full RunUO-parity move table (`CurrentMoveSpeed * 1000`). Medium-bucket pets (Horse, Dog, most tamables): passiveMove **1.05s/step**.
- Pet order speed depended on stale `Warmode`: `HandleGuardOrder` set it once, but `OnCombatantChange` clears it whenever the combatant drops, so obedience ran active or passive **by combat history** — usually passive. Net: Guard/Come at ~1.05s/step (~2.1x slower than pre-#2591), vs a player running at 0.1–0.2s/step.
- The AITimer never rescheduled its pending wheel entry: the wheel reads `Interval` only after the next fire, so a speed-up or a fresh order (`Activate()` no-ops while running) waited out the stale wake — up to a full passive think, stacked on the residual move budget on Guard → Follow.
**What changed:**
- **Order handlers own obedience speed** (RunUO `OnCurrentOrderChanged`/`DoOrder*` parity, re-derived continuously): issuing a movement order (Come/Follow/Guard/Attack) sets the **active** think clock, resting orders (Stay/None/Transfer) set passive, and the guard/follow peaceful branches write **RunUO's AOS `CurrentSpeed = 0.1` sprint** — RunUO's guard else-branch had the identical write as follow. The bespoke 0.1 fuses to both clocks through #2591's existing classification, so `CurrentMoveSpeed` stays **pure herding + classification** with no obedience special case, and `DoMoveImpl`'s per-step flip skips obeying pets (their handler owns the pace) and loses its old follow-only 0.1 write. Combat still re-derives organically via warmode/combatant.
- **`AITimer`**: tracks the pending wake and reschedules (`Stop`, `Delay` = remaining, `Start`) when a speed-up or fresh order moves the earliest deadline up; changes inside a tick still flow through `ScheduleNext`. New `Prod()` wakes the AI immediately on player commands — including from a stopped timer, so stable claims no longer wait out the random construction stagger. Sector/spawn wakes keep the stagger. Spam-safe: a prodded think grants reaction, never action — steps/swings/casts/abilities are gated by their own budgets and timers.
The residual move budget is deliberately **not** cleared on order change — that would let order-spam macros grant free steps. Deadline changes reschedule the timer; rate changes take effect at the next deadline computation.
## #2595 — Guard order converts to Attack during combat
**Why:** `FindCombatant()` set `ControlOrder = OrderType.Attack` when engaging, so a guarding pet left the Guard order for the whole fight: OPL tags wiped (pet `1080078` + master `501129`), no retargeting (`DoOrderAttack` locks its target), `TeleportPets` left the pet behind on recall/gate, and every engage→kill→resume cycle replayed the guard flourish.
**What changed:**
- **`FindGuardTarget()`** (was `FindCombatant`): a pure selector — prefers the aggressor **closest to the master** (RunUO guard parity, dynamic retargeting to protect the owner), keeps the current combatant unless a strictly closer one exists, and never mutates order state. `DoOrderGuard` engages through it while **staying in Guard** the whole fight.
- **Persistent-order semantics** (the ModernUO improvement over RunUO): an explicit `all attack` completes → `ResumePersistentOrder()` returns to Guard → the guard scan engages remaining threats in-order. The Attack-chaining fallback (`FightMode.Closest/Aggressor`) now applies only to non-guard persistent orders. Resuming Guard no longer replays the sound/"is now guarding you" message.
- **Peaceful guard stands down deterministically** (`Warmode`/`Combatant`/`FocusMob` cleared) and returns to the master at the RunUO sprint (see above); at the master's side it stays organically active.
- **`WalkMobileRange` honors the caller's run flag** (the internal hardcoded `dist > 5` gate silently overrode it). Run is animation-only server-side; the only callers passing anything but `false` — follow, guard, clone — gate on their own thresholds.
## Resulting behavior (Medium-bucket pet)
| Scenario | Broken | This PR |
|---|---|---|
| Guard trailing master (AOS) | ~1.05s/step, think-grid quantized | 0.1s/step sprint (RunUO parity), smooth move wakes |
| Guard during combat | order flips to Attack; tags lost; no retarget; left behind on recall | stays Guard; retargets to master's closest aggressor; teleports with master |
| `all attack` while guarding | resume spams guard flourish per kill; chains into Attack | resumes Guard silently; guard scan takes over |
| Come / friend-follow | 1.05s/step | activeMove 0.45s/step (≈ pre-#2591 feel) |
| Guard → Follow reaction | up to ~1.5s dead time | think within one wheel turn |
| Follow master (AOS sprint) | 0.1s/step | 0.1s/step (unchanged) |
| Wild creature chase | RunUO-parity move table | unchanged |
Also documents two contracts this work leaned on: the `ControlOrder` setter deliberately fires on every assignment (a reissued order is a command — retarget/break-off/re-anchor), and `OnThink`/`MonsterAbility` must be excess-call tolerant (`dev-docs/content-patterns.md` § OnThink: the excess-call contract).
## Testing
- Full suite passes (1570: 837 Server + 733 UOContent).
- `PetPacingTests`: order-issue think-clock parity, follow-master sprint via Obey, guard organically active at the master's side, combat-chase and herding boundaries, plus two deterministic timer-wheel tests (8ms-lockstep slicing) proving a fresh order and a mid-wait speed-up wake the AI promptly.
- `GuardOrderTests`: engage keeps the Guard order; retargets to the aggressor closest to the master; explicit attack resumes Guard without chaining into Attack; peaceful guard stands down. Setup self-validates LOS/terrain.
- `GuardFollowTests`: guard-following registers a move intent, steps toward the master, sprints at 0.1 under AOS (per-step flip must not undo it), and runs active pre-AOS.
- All behavioral tests were written first and failed for the documented reasons.
Splits creature speed into two clocks so movement pace can be tuned without touching reaction time:
- **Think clock** — `ActiveSpeed`/`PassiveSpeed`/`CurrentSpeed`: seconds per AI decision. Unchanged in meaning, storage, and cadence.
- **Move clock** — `ActiveMoveSpeed`/`PassiveMoveSpeed` (+ resolved `CurrentMoveSpeed`): seconds per step. `0` = inherit the matching think value.
### How
- Move speeds come from optional `activeMove`/`passiveMove` in `npc-speeds.json`, are `[props`-tunable per instance (set `0` to re-inherit), and serialize (BaseCreature v22).
- `SetSpeed()` keeps its legacy one-clock semantics — sets the think clock **and clears move overrides** — so existing callers cannot half-configure a creature. `SetMoveSpeed()`/`ClearMoveSpeed()` configure movement explicitly; `ScaleMoveSpeed()` scales overrides for buffs.
- `CurrentMoveSpeed` is derived by classifying `CurrentSpeed`: a verbatim active/passive think value maps to the matching move value; a bespoke pace written directly (mount boosts, follow sprint) stays fused to both clocks. External `CurrentSpeed` writers need no changes.
- `AITimer` schedules the earlier of the two deadlines. Decisions run at the think cadence exactly as before; while a pursuit/investigation is live, the timer also wakes when the movement budget elapses and advances one step with no decisions. Steps no longer snap to the think grid, so any step delay paces smoothly on the 8ms wheel. A blocked creature schedules no move wakes.
- The movement budget is RunUO's `m_NextMove` accumulate-and-clamp at a full step, so long-run pacing averages `CurrentMoveSpeed` exactly.
### Behavior changes
- **`npc-speeds.json` buckets get RunUO `TransformMoveDelay`-parity move values**: creatures step at RunUO pace while thinking/reacting at current speed. The situational +0.1/+0.2 offsets are deliberately omitted.
- **Existing saves migrate on load**: a pre-v22 creature whose think speeds still match its npc-speeds entry (never hand-tuned) adopts the table's move values — worlds and pets pick up the new pacing without a respawn. Tuned creatures keep movement inheriting their think clock.
- **Paragons scale movement by `SpeedBuff` (1.2x)**: RunUO had no deliberate policy here — dividing by 1.2 knocked most speeds off `TransformMoveDelay`'s exact-equality table (raw pass-through, 2x+ faster), while 0.3/0.6 creatures landed back on it for ~1.33x. This applies the uniform 1.2x the buff always claimed. UnConvert snaps speeds back to exact table values within 1e-4 — /1.2 then ×1.2 drifts 0.45 and 0.9 by an ulp, which would read as hand-tuned (and defeat a future skip-table-conformant-values serialization pass); tuned speeds keep.
- **Herding paces the movement clock**: the old `CurrentSpeed` getter hack is gone. A herded creature walks at a fixed 0.3s/step — RunUO's forced pace, without its `TransformMoveDelay` inflation to 0.6 — so herding is never penalized by a slow creature. Thinking is untouched, and `CheckHerding` walks through `MoveToPoint`, so herded creatures path around obstacles.
- **Badly-hurt slowdown now inflates the step delay only** (RunUO parity), computed from the base each step. Previously it wrote `CurrentSpeed = CurrentSpeed + 0.05..0.15` back on every successful step — compounding unboundedly while hurt and slowing decisions too.
- Removes the vestigial `MoveSpeedMod` (never read, written, or serialized).
- With no bucket or per-instance move values, both clocks carry identical values and creatures pace as before.
### Testing
- Full suite passes (1557, including 12 new `MoveSpeedTests`: resolution classes, `SetSpeed` clearing, `0`-re-inherit, v22 round-trip with exact-consumption check, save migration adopt/skip, buff scale/snap, herding).
- In-game verified via local diagnostics build (per-step budget tracing): steady 700ms step cadence on a 0.3s think grid with one-step catch-up after idle, think grid unperturbed by move wakes.
### Summary
Fixes the long-standing reports of monsters losing track of players who run around a corner ("Is monster AI not using pathfinding? It seems to be LOS blocked by statics"). Root-cause investigation compared current behavior against RunUO line-by-line and traced the regressions through the AI overhaul era (#2232, #2246, #2379, #2401, #2461).
### Root causes and fixes
1. **Movement contract** — `MoveTo`/`ApproachTarget` returned false on every healthy mid-chase tick (true only on arrival), so MeleeAI's RunUO-inherited *"move failed and beyond RangePerception+1 → Guard"* clause — which RunUO only evaluated on genuine blockage — fired **every tick of every chase**. A mounted player trivially opens 17 tiles at a corner, the monster guards, Guard nulls the combatant, and re-acquisition is LOS-gated — unrecoverable through a wall. Movement now reports failure only on genuine failure (no step taken with no working path, or approach give-up). ArcherAI's equivalent clause moves to the hard leash.
2. **Last-known-position pursuit** — while a combatant is in LOS its position is recorded each think tick. When the target vanishes (corner, hiding, recall), the creature walks to the last-seen spot, stands guard there ~10s (restoring RunUO's guard grace, which had decayed to a single tick since #2246), and **re-engages instantly** if the same target re-enters view — bypassing the 10s reacquire throttle.
3. **`ChaseLeashRange`** — new virtual on BaseCreature (default `RangePerception * 2` = 32 tiles) replaces the inline `RangePerception * 3` (48) in Melee/Mage/Archer AI. Per-creature tunable via `[props`.
4. **Group movement demoted to a crowding refinement** — previously any uncontrolled creature with one ally within 8 tiles on the same target used greedy ring-stepping for the *entire* chase, with wall-slides counted as success, never invoking the pathfinder — the "aggroed but won't come around the corner" symptom for spawn groups. It now engages only near the target when allies actually contest the ring, and blocked/wall-slid steps escalate to the pathfinding approach primitive.
5. **Mages close distance on broken LOS** — a mage within casting range but LOS-blocked by geometry stood at the wall holding a spell target until the 60s combatant expiry (ProcessTarget short-circuits Think and its RunTo stands off at RangeFight). Geometry-blocked mages now close in until LOS returns, both pre-cast and while holding a target. Hidden targets (CanSee) and poison-cure priority unchanged. The new movement contract also stops the constant spurious `OnFailedMove` teleport rolls mid-chase.
6. **Move budget: one actual step per AI tick** — nothing advanced `NextMove` on a normal step (RunUO's `m_NextMove` budget was lost), so code paths attempting several moves in one think tick could cross multiple tiles at once — visible as "warping" when crowded creatures jockey for position. A successful step now consumes a half-step budget (floor 50ms): blocks intra-tick double moves, stays safely below the timer interval so legitimate next-tick moves are never jitter-throttled, and does not reintroduce `TransformMoveDelay` inflation. Blocked attempts consume nothing, so retry ladders (repath-and-step, the collision fan) are unaffected. `CanMoveNow` is also wraparound-safe now.
### Reference behavior
RunUO requires LOS to *acquire* a target and to *land* a hit or spell — never to *continue* a chase (its MeleeAI LOS bail-out is literally commented out in stock code). Chases drop only on: target hidden, target dead/off-map, beyond `RangePerception * 3`, 60s without combat interaction, or blocked movement while far away. This PR restores those semantics while adding the last-known-position investigation on top. NPC run flags are untouched — pace is AI-timer-driven and most NPC art has no run animation.
## Summary
- Fixes pets falling behind mounted masters in AOS+ by setting `CurrentSpeed = 0.1` when following master
- Fixes AI timer permanently stopping when `Obey()`/`Think()` returns `false` for transient conditions
- Fixes controlled pets losing AI in inactive sectors (pet follows owner across sector boundary, sector deactivates, AI dies)
- Adds defense-in-depth: AI timer restarts on pet resurrection and order changes
## AI Timer Permanent Stop (Bug Fix)
`AITimer.OnTick()` called `Stop()` when `Obey()` or `Think()` returned `false`. By that point, `ShouldStop()` had already validated the creature is alive, on a valid map, and in an active sector — so any `false` return was a **transient** condition, not terminal. The timer stopped permanently with no mechanism to restart it.
**Scenarios that triggered permanent AI death:**
- Dead bonded pet with attack order (`DoOrderAttack` returned `false` for `IsDeadPet`)
- Failed pet transfer — loyalty refusal, combat, disconnected player, or pending trade (`DoOrderTransfer` returned `false` for 5 different transient conditions)
- Unknown `OrderType` or `ActionType` (defensive defaults)
**Fixes:**
- Removed `Stop()` from the `Obey()`/`Think()` failure path — timer skips the tick and fires again next interval
- Changed `DoOrderAttack()` and all five `DoOrderTransfer()` failure paths to return `true` (correct semantics: these are recoverable states, not "stop AI forever" signals)
- Added `Activate()` call in `ResurrectPet()` — ensures dead bonded pets have AI running after resurrection
- Added `Activate()` call in `OnCurrentOrderChanged()` — self-heals timer if any voice command is issued to a pet with a stopped timer
## Controlled Pet Sector Deactivation (Bug Fix)
`ShouldStop()` stopped the AI timer for **all** `PlayerRangeSensitive` creatures in inactive sectors, including controlled pets. But `Deactivate()` intentionally exempted controlled pets. The exemption was dead code — `ShouldStop()` bypassed it.
This matters when a pet follows its owner across a sector boundary: the owner enters the next sector (active), the pet's old sector deactivates (no more players), and the pet's AI dies. The pet stops following and stands there until the player backtracks far enough to reactivate the sector.
**Fix:** Added `Controlled` check to `ShouldStop()` to match `Deactivate()`. Controlled pets now keep their AI running in inactive sectors. The overhead is negligible — controlled pets are bounded by follower slots.
## Movement Speed Simplification
- Simplifies `AITimer` to use `CurrentSpeed` directly as the tick interval (in seconds), removing the complex multiplier/floor logic in `GetBaseInterval`
- Refactors `DoMoveImpl` speed assignment into explicit if/else for clarity
- AOS+ pets following master use `CurrentSpeed = 0.1` (100ms), matching `RunMountDelay`
## Files Changed
- `AITimer.cs` — removed `Stop()` on Obey/Think failure, added `Controlled` exemption to `ShouldStop()`, simplified interval logic
- `BaseAI.cs` — renamed `_timer` to `AITimer` (public), simplified `Deactivate()`, fixed `ReturnToHome` to use `Activate()`
- `PetOrders.cs` — `DoOrderAttack` and `DoOrderTransfer` return `true` for transient failures
- `PetOrderHandlers.cs` — `OnCurrentOrderChanged()` calls `Activate()` to self-heal stopped timers
- `BaseCreature.cs` — `ResurrectPet()` calls `Activate()`, fixed `GoHome_Callback` PlayerRangeSensitive check
- `AIMovement.cs` — refactored speed assignment, AOS+ follow-master speed fix
### Summary
This PR transitions the spawner system from a simple radius-based model to a flexible 3D boundary system.
### Core Changes
* **Replaced `HomeRange` with `SpawnBounds`**: Spawners now use a `Rectangle3D` to define spawn areas instead of a circular integer range.
* **Backward Compatibility**:
* The `HomeRange` property remains as a helper that generates square `SpawnBounds` centered on the spawner.
* Included a migration path (v10 to v11) that automatically converts old range data into new bounds during deserialization.
* **Dynamic Bounds Shifting**: If a spawner is moved, its `SpawnBounds` will automatically shift with it, provided the bounds are currently configured as a centered square.
* **New Spawn Logic**: Added `SpawnLocationIsHome` toggle. If enabled, spawned mobiles treat their exact spawn coordinates as their "Home" rather than the spawner's location.
### Implementation Details
* **Interface Updates**: Updated `ISpawner` to include `WalkingRange`, `SpawnBounds`, and `IsInSpawnBounds()`.
* **UI Enhancements**: The Spawner Controller Gump now displays "Custom" for complex bounds and allows copying of the new boundary properties between spawners.
* **Refactored Constructors**: Streamlined `BaseSpawner`, `ProximitySpawner`, and `RegionSpawner` constructors to support the new data types.
### Summary
* Refactors AI so it is easier to read and maintain
* Fixes NPC speed issues
* Fixes pet sector AI issue that was causing stuttering
* Fixes direction snapping for Melee/Mage AI
* Refactors pet orders
* Refactors speech commands
* Removes scale speed by dex for HS+ (it was a stupid feature anyways)