diff --git a/YAMS-LIB/Program.cs b/YAMS-LIB/Program.cs
index e75daf5..530c4ac 100644
--- a/YAMS-LIB/Program.cs
+++ b/YAMS-LIB/Program.cs
@@ -596,6 +596,7 @@ public static void Main(string am2rPath, string outputAm2rPath, string jsonPath)
 
         // Multiworld stuff
         Multiworld.Apply(gmData, decompileContext, seedObject);
+        AddBossMWTracking.Apply(gmData, decompileContext, seedObject);
 
         // Write back to disk
         using (FileStream fs = new FileInfo(outputAm2rPath).OpenWrite())
diff --git a/YAMS-LIB/patches/AddBossMWTracking.cs b/YAMS-LIB/patches/AddBossMWTracking.cs
new file mode 100644
index 0000000..30145cf
--- /dev/null
+++ b/YAMS-LIB/patches/AddBossMWTracking.cs
@@ -0,0 +1,30 @@
+using UndertaleModLib;
+using UndertaleModLib.Decompiler;
+using UndertaleModLib.Models;
+
+namespace YAMS_LIB.patches;
+
+public class AddBossMWTracking
+{
+    public static void Apply(UndertaleData gmData, GlobalDecompileContext decompileContext, SeedObject seedObject)
+    {
+        // Guardian
+        gmData.Code.ByName("gml_Object_oBoss1Head_Step_0").ReplaceGMLInCode("sfx_play(sndBoss1Death)", "sfx_play(sndBoss1Death); global.collectedItems += \"Guardian|1,\"; send_location_and_inventory_packet();");
+        gmData.Code.ByName("gml_Object_oBoss1Head_Collision_382").ReplaceGMLInCode("sfx_play(sndBoss1Death)", "sfx_play(sndBoss1Death); global.collectedItems += \"Guardian|1,\"; send_location_and_inventory_packet();");
+
+        // Arachnus
+        gmData.Code.ByName("gml_Object_oArachnus_Step_0").ReplaceGMLInCode("sfx_play(sndArachnusDeath)", "sfx_play(sndArachnusDeath); global.collectedItems += \"Arachnus|1,\"; send_location_and_inventory_packet();");
+
+        // Torizo
+        gmData.Code.ByName("gml_Object_oTorizo2_Step_0").ReplaceGMLInCode("sfx_play(sndTorizoDeath)", "{ sfx_play(sndTorizoDeath); global.collectedItems += \"Torizo|1,\"; send_location_and_inventory_packet(); }");
+
+        // Tester
+        gmData.Code.ByName("gml_Object_oTester_Step_0").ReplaceGMLInCode("sfx_play(sndTesterDeath)", "sfx_play(sndTesterDeath); global.collectedItems += \"Tester|1,\"; send_location_and_inventory_packet();");
+
+        // Serris
+        gmData.Code.ByName("gml_Object_oErisHead_Step_0").ReplaceGMLInCode("sfx_play(sndErisDeath)", "sfx_play(sndErisDeath); global.collectedItems += \"Serris|1,\"; send_location_and_inventory_packet();");
+
+        // Genesis
+        gmData.Code.ByName("gml_Object_oGenesis_Step_0").ReplaceGMLInCode("sfx_play(sndGenesisDeath)", "sfx_play(sndGenesisDeath); global.collectedItems += \"Genesis|1,\"; send_location_and_inventory_packet();");
+    }
+}