ModernUO/dev-docs/claude-skills/modernuo-era-expansion.md

name	description
modernuo-era-expansion	Trigger when writing era-conditional code, using Core.AOS/SE/ML etc., or when user hasn't specified target era. Always ask which expansion to target if not specified.

ModernUO Era & Expansion Support

When This Activates

• Writing code that depends on game era (damage formulas, skill caps, mechanics)
• Using Core.AOS, Core.SE, Core.ML, etc.
• User asks for a feature without specifying era
• Implementing mechanics that changed across expansions

CRITICAL RULE

Never assume era. If the user hasn't specified which expansion to target, ASK before writing era-dependent code.

Expansion Enum

public enum Expansion
{
    None,    // 0 - Pre-T2A
    T2A,     // 1 - The Second Age
    UOR,     // 2 - Renaissance
    UOTD,    // 3 - Third Dawn
    LBR,     // 4 - Blackthorn's Revenge
    AOS,     // 5 - Age of Shadows (major overhaul)
    SE,      // 6 - Samurai Empire
    ML,      // 7 - Mondain's Legacy
    SA,      // 8 - Stygian Abyss
    HS,      // 9 - High Seas
    TOL,     // 10 - Time of Legends
    EJ       // 11 - Endless Journey
}

Era Check Properties

Each returns true when Core.Expansion >= that era:

Core.T2A   // >= The Second Age
Core.UOR   // >= Renaissance
Core.UOTD  // >= Third Dawn
Core.LBR   // >= Blackthorn's Revenge
Core.AOS   // >= Age of Shadows
Core.SE    // >= Samurai Empire
Core.ML    // >= Mondain's Legacy
Core.SA    // >= Stygian Abyss
Core.HS    // >= High Seas
Core.TOL   // >= Time of Legends
Core.EJ    // >= Endless Journey

For exact expansion: Core.Expansion == Expansion.AOS

Key Era Boundaries

AOS (Age of Shadows) -- Most Significant Change

• Complete combat overhaul: resistance-based damage system
• Property-based item system (magic properties)
• New damage formula: GetNewAosDamage() vs flat Utility.Random()
• Luck system for loot
• Insurance system

SE (Samurai Empire)

• Bushido / Ninjitsu skills
• Samurai/Ninja classes
• Loot pack adjustments

ML (Mondain's Legacy)

• Spellweaving
• Adjusted skill gain chances
• Container weight display changes

Pattern: Era-Conditional Code

// Ternary for simple values
var delay = Core.SE ? 250 : Core.AOS ? 500 : 1000;

// If/else for logic branches
if (Core.AOS)
{
    damage = GetNewAosDamage(10, 1, 4, target);
}
else
{
    damage = Utility.Random(4, 4);
    if (CheckResisted(target))
        damage *= 0.75;
}

// Property display varies by era
if (Core.ML)
{
    list.Add(1072241, $"{TotalItems}\t{MaxItems}\t{TotalWeight}\t{MaxWeight}");
}
else
{
    list.Add(1050044, $"{TotalItems}\t{TotalWeight}");
}

Pattern: Era-Dependent Loot

LootPack properties auto-select based on expansion:

// These automatically pick the right era variant
LootPack.Poor       // OldPoor / AosPoor / SePoor
LootPack.Average    // OldAverage / AosAverage / SeAverage
LootPack.Rich       // OldRich / AosRich / SeRich
LootPack.FilthyRich // OldFilthyRich / AosFilthyRich / SeFilthyRich
LootPack.UltraRich  // OldUltraRich / AosUltraRich / SeUltraRich

Anti-Patterns

• Hardcoding mechanics for one era without conditional checks
• Assuming AOS when the user might want pre-AOS
• Using era-specific APIs without checking (e.g., GetNewAosDamage() pre-AOS)

Real Examples

• Era-conditional damage: Projects/UOContent/Spells/First/MagicArrow.cs
• Era-conditional properties: Projects/Server/Items/Container.cs (GetProperties)
• Era-conditional values: Projects/UOContent/Items/Weapons/Ranged/BaseRanged.cs
• Expansion enum: Projects/Server/ExpansionInfo.cs
• Stat config by era: Projects/UOContent/Skills/SkillCheck.cs

See Also

• dev-docs/era-expansion.md - Complete expansion documentation
• dev-docs/claude-skills/modernuo-content-patterns.md - Content templates
• dev-docs/claude-skills/modernuo-configuration.md - Configuration system