Init forge support only for valid contracts

src/engine/net/client/msg/ManageNPCMsg.java

@@ -434,10 +434,6 @@ public class ManageNPCMsg extends ClientNetMsg {
                             writer.put((byte) template.modTable);//EffectItemType
                         }
 
-                        // Sanity check.
-
-                        ForgeManager.vendorItemLookup.computeIfAbsent(npc, k -> new ArrayList<>()); // Forge lookup
-
                         writer.putInt(ForgeManager.vendorItemLookup.get(npc).size());
 
                         for (Item item : ForgeManager.vendorItemLookup.get(npc)) {

src/engine/objects/NPC.java

@@ -869,6 +869,11 @@ public class NPC extends AbstractCharacter {
         if (this.building != null)
             NPCManager.slotCharacterInBuilding(this);
 
+        // If NPC is a vendor create arraylist for forge
+
+        if (this.contract.isTrainer() == false)
+            ForgeManager.vendorItemLookup.computeIfAbsent(this, k -> new ArrayList<>()); // Forge lookup
+
         this.symbol = this.contract.getIconID();
         this.modTypeTable = this.contract.getNPCModTypeTable();
         this.modSuffixTable = this.contract.getNpcModSuffixTable();