Fixed replacementattack not being complete.

src/Battling/Models/BattleSide.cpp

@@ -68,3 +68,7 @@ void BattleSide::GetActiveScripts(std::vector<ScriptWrapper>& scripts) {
     scripts.emplace_back(&_volatile);
     _battle->GetActiveScripts(scripts);
 }
+uint8_t BattleSide::GetRandomCreatureIndex() {
+    // TODO: Consider adding parameter to only get index for available creatures.
+    return _battle->GetRandom()->Get(_creaturesPerSide);
+}