fix: issues #221 #217 #225 #227 #224 #226 - crafting refunds, mana tracking, cancel slot, multi-element guardians, spell kill advance

src/lib/game/utils/combat-utils.ts

@@ -50,6 +50,17 @@ export function getElementalBonus(spellElem: string, floorElem: string): number
   return 1.0; // Neutral
 }
 
+/**
+ * Get the elemental bonus against a multi-element floor/guardian.
+ * Uses the minimum bonus across all elements so multi-element guardians
+ * are not trivially countered (each element can resist different spells).
+ */
+export function getMultiElementBonus(spellElem: string, floorElems: string[]): number {
+  if (floorElems.length === 0) return 1.0;
+  if (floorElems.length === 1) return getElementalBonus(spellElem, floorElems[0]);
+  return Math.min(...floorElems.map(e => getElementalBonus(spellElem, e)));
+}
+
 // ─── Boon Bonuses ─────────────────────────────────────────────────────────────
 
 export interface BoonBonuses {

src/lib/game/utils/index.ts

@@ -18,6 +18,7 @@ export {
 // computeElementMax is now in ../store.ts with support for unlockedManaTypeUpgrades
 export { 
   getElementalBonus, 
+  getMultiElementBonus,
   getBoonBonuses, 
   calcDamage, 
   calcInsight,