diff --git a/CInterface/Battling/BattleParty.cpp b/CInterface/Battling/BattleParty.cpp
index dd40f29..104d590 100644
--- a/CInterface/Battling/BattleParty.cpp
+++ b/CInterface/Battling/BattleParty.cpp
@@ -7,7 +7,7 @@ using namespace CreatureLib::Battling;
 export uint8_t CreatureLib_BattleParty_Construct(BattleParty*& out, CreatureParty* p, uint8_t creatureIndices[],
                                                  size_t numberOfIndices) {
     Try(ArbUt::List<CreatureIndex> indices(numberOfIndices); for (size_t i = 0; i < numberOfIndices; i++) {
-        indices[i] = CreatureIndex(creatureIndices[i * 2], creatureIndices[i * 2 + 1]);
+        indices.Append(CreatureIndex(creatureIndices[i * 2], creatureIndices[i * 2 + 1]));
     } out = new BattleParty(p, indices);)
 }