Feature 17: Gear Enhancement & Reforging

Overview

Endgame item progression: enhancement (+1 to +5 upgrades that increase base stats) and reforging (re-roll random bonus properties on Rare+ items). Both are material and gold sinks that give max-level players long-term goals without adding power creep.

Dependencies

• Feature 03 (Items & Inventory) — gear with bonus properties
• Feature 08 (Crafting) — crafting materials used as enhancement/reforge inputs
• Feature 09 (Economy) — gold sinks

Technical Tasks

1. Enhancement Logic (crates/game)

• Create src/enhancement.rs:
  • Enhancement levels: +1 through +5
  • Per level: material cost, gold cost, success chance
    • +1: 5 Uncommon Shards, 500 gold, 100% success
    • +2: 10 Uncommon Shards + 2 Rare Cores, 2000 gold, 80% success
    • +3: 5 Rare Cores, 5000 gold, 60% success
    • +4: 10 Rare Cores + 2 Prismatic Essences, 15000 gold, 40% success
    • +5: 5 Prismatic Essences + 1 Legendary Spark, 50000 gold, 20% success
  • Failure: item stays at current level (no downgrade), materials consumed
  • enhance_item(item: &Item, target_level: u8, rng: &mut impl Rng) -> EnhanceResult:
    • Check current enhancement < target
    • Roll success chance
    • Return Success(new_level) or Failure(current_level)
  • enhancement_stat_bonus(base_stat: u16, level: u8) -> u16:
    • +5% per level to base damage/armor/evasion

2. Reforging Logic (crates/game)

• Create src/reforging.rs:
  • Only available for Rare+ items (they have random bonus properties)
  • reforge_cost(rarity: Rarity) -> ReforgeCost:
    • Rare: 3 Rare Cores + 1000 gold
    • Very Rare: 5 Rare Cores + 2 Prismatic Essences + 5000 gold
    • Legendary: 3 Prismatic Essences + 1 Legendary Spark + 20000 gold
  • reforge_item(item: &mut Item, rng: &mut impl Rng) -> Vec<BonusProperty>:
    • Re-roll ALL random bonus properties (keep count, re-roll values and types)
    • Signature effect is NOT re-rolled (it’s fixed per template)
    • Return new bonus properties

3. API Routes (crates/api)

• Add to src/routes/inventory.rs:
  • POST /api/characters/:id/enhance:
    • Body: { item_id }
    • Validate: item owned, enhancement < 5, has materials + gold
    • Deduct materials and gold
    • Roll enhancement
    • Return { success, new_enhancement_level }
  • POST /api/characters/:id/reforge:
    • Body: { item_id }
    • Validate: item owned, Rare+ rarity, has materials + gold
    • Deduct materials and gold
    • Re-roll bonuses
    • Return { new_bonus_properties }

4. Client — Enhancement & Reforging UI

• Add to inventory screen:
  • “Enhance” button on eligible items → modal showing cost, success chance, current level
  • “Reforge” button on Rare+ items → modal showing cost, current bonuses, warning about random results
  • Enhancement level displayed on item: “+3 Iron Longsword”
  • Visual indicator of enhancement level (glow effect or badge)

Tests

Unit Tests

• enhance_item: +1 always succeeds (100%)
• enhance_item: +5 has 20% success rate (statistical test with seeded RNG)
• enhance_item: failure doesn’t downgrade
• enhancement_stat_bonus: +5 at level 3 = +15% bonus
• reforge_item: keeps same number of bonus properties
• reforge_item: can produce different properties than original
• reforge_item: deterministic with seeded RNG
• reforge_cost: correct per rarity tier

Integration Tests

• POST /api/characters/:id/enhance deducts materials and gold
• POST /api/characters/:id/enhance on max (+5) → 409
• POST /api/characters/:id/enhance with insufficient materials → 422
• POST /api/characters/:id/reforge re-rolls bonuses, deducts cost
• POST /api/characters/:id/reforge on Common item → 422
• Enhanced item stats correctly increased in equipment calculations