diff --git a/extensions/Lily/CollisionTags.js b/extensions/Lily/CollisionTags.js
new file mode 100644
index 0000000000..127cd7c1df
--- /dev/null
+++ b/extensions/Lily/CollisionTags.js
@@ -0,0 +1,250 @@
+(function (Scratch) {
+  "use strict";
+
+  const vm = Scratch.vm;
+  const runtime = vm.runtime;
+  const Cast = Scratch.Cast;
+
+  class CollisionTags {
+    constructor() {
+      for (const target of runtime.targets) {
+        target._collisionTags = [];
+      }
+    }
+    getInfo() {
+      return {
+        id: "lmsCollisions",
+        name: "Collision Tags",
+        color1: "#5cb1d6",
+        color2: "#47a8d1",
+        color3: "#2e8eb8",
+        blocks: [
+          {
+            opcode: "addTag",
+            blockType: Scratch.BlockType.COMMAND,
+            text: "add tag [TAG] to [TARGET]",
+            arguments: {
+              TAG: {
+                type: Scratch.ArgumentType.STRING,
+              },
+              TARGET: {
+                type: Scratch.ArgumentType.STRING,
+                menu: "targets",
+              },
+            },
+          },
+          {
+            opcode: "removeTag",
+            blockType: Scratch.BlockType.COMMAND,
+            text: "remove tag [TAG] from [TARGET]",
+            arguments: {
+              TAG: {
+                type: Scratch.ArgumentType.STRING,
+              },
+              TARGET: {
+                type: Scratch.ArgumentType.STRING,
+                menu: "targets",
+              },
+            },
+          },
+          {
+            opcode: "removeAllTags",
+            blockType: Scratch.BlockType.COMMAND,
+            text: "remove all tags from [TARGET]",
+            arguments: {
+              TARGET: {
+                type: Scratch.ArgumentType.STRING,
+                menu: "targets",
+              },
+            },
+          },
+          {
+            opcode: "getTagsOfSprite",
+            blockType: Scratch.BlockType.REPORTER,
+            text: "collision tags of [TARGET]",
+            arguments: {
+              TARGET: {
+                type: Scratch.ArgumentType.STRING,
+                menu: "targets",
+              },
+            },
+          },
+          "---",
+          {
+            opcode: "touchingTargetWithTag",
+            blockType: Scratch.BlockType.BOOLEAN,
+            text: "touching [TYPE] of [TARGET] with tag [TAG]?",
+            arguments: {
+              TYPE: {
+                type: Scratch.ArgumentType.STRING,
+                menu: "types",
+              },
+              TARGET: {
+                type: Scratch.ArgumentType.STRING,
+                menu: "targets",
+              },
+              TAG: {
+                type: Scratch.ArgumentType.STRING,
+              },
+            },
+          },
+          {
+            opcode: "touchingWithTag",
+            blockType: Scratch.BlockType.BOOLEAN,
+            text: "touching [TYPE] with tag [TAG]?",
+            arguments: {
+              TYPE: {
+                type: Scratch.ArgumentType.STRING,
+                menu: "types",
+              },
+              TAG: {
+                type: Scratch.ArgumentType.STRING,
+              },
+            },
+          },
+        ],
+        menus: {
+          // Targets have acceptReporters: false
+          types: {
+            acceptReporters: false,
+            items: ["parent", "clone", "anything"],
+          },
+          // Targets have acceptReporters: true
+          targets: {
+            acceptReporters: true,
+            items: "_getTargets",
+          },
+        },
+      };
+    }
+
+    addTag(args, util) {
+      const targetName = Cast.toString(args.TARGET);
+      const tag = Cast.toString(args.TAG);
+      const target = this._getTargetFromMenu(targetName, util);
+      if (!target) return;
+
+      if (!target._collisionTags) target._collisionTags = [];
+      if (target._collisionTags.includes(tag) || tag === "") return;
+
+      target._collisionTags.push(tag);
+    }
+
+    removeTag(args, util) {
+      const targetName = Cast.toString(args.TARGET);
+      const tag = Cast.toString(args.TAG);
+      const target = this._getTargetFromMenu(targetName, util);
+      if (!target) return;
+
+      if (!target._collisionTags || !target._collisionTags.includes(tag))
+        return;
+
+      const index = target._collisionTags.indexOf(tag);
+      target._collisionTags.splice(index, 1);
+    }
+
+    removeAllTags(args, util) {
+      const targetName = Cast.toString(args.TARGET);
+      const target = this._getTargetFromMenu(targetName, util);
+      if (!target) return;
+
+      target._collisionTags = [];
+    }
+
+    getTagsOfSprite(args, util) {
+      const targetName = Cast.toString(args.TARGET);
+      const target = this._getTargetFromMenu(targetName, util);
+
+      if (!target || !target._collisionTags) return "[]";
+      return JSON.stringify(target._collisionTags);
+    }
+
+    touchingTargetWithTag(args, util) {
+      const targetName = Cast.toString(args.TARGET);
+      const type = Cast.toString(args.TYPE);
+      const tag = Cast.toString(args.TAG);
+      const target = this._getTargetFromMenu(targetName, util);
+      if (!target) return;
+
+      let drawableCandidates;
+      if (type === "parent") drawableCandidates = [target];
+      if (type === "anything")
+        drawableCandidates = target.sprite.clones.filter(
+          (target) =>
+            target._collisionTags && target._collisionTags.includes(tag)
+        );
+      if (type === "clone")
+        drawableCandidates = target.sprite.clones.filter(
+          (target) =>
+            target._collisionTags &&
+            target._collisionTags.includes(tag) &&
+            !target.isOriginal
+        );
+      drawableCandidates = drawableCandidates.map(
+        (target) => target.drawableID
+      );
+
+      return vm.renderer.isTouchingDrawables(
+        util.target.drawableID,
+        drawableCandidates
+      );
+    }
+
+    touchingWithTag(args, util) {
+      const type = Cast.toString(args.TYPE);
+      const tag = Cast.toString(args.TAG);
+
+      let drawableCandidates;
+      if (type === "parent")
+        drawableCandidates = runtime.targets.filter(
+          (target) =>
+            target._collisionTags &&
+            target._collisionTags.includes(tag) &&
+            target.isOriginal
+        );
+      if (type === "anything")
+        drawableCandidates = runtime.targets.filter(
+          (target) =>
+            target._collisionTags && target._collisionTags.includes(tag)
+        );
+      if (type === "clone")
+        drawableCandidates = runtime.targets.filter(
+          (target) =>
+            target._collisionTags &&
+            target._collisionTags.includes(tag) &&
+            !target.isOriginal
+        );
+      drawableCandidates = drawableCandidates.map(
+        (target) => target.drawableID
+      );
+
+      return vm.renderer.isTouchingDrawables(
+        util.target.drawableID,
+        drawableCandidates
+      );
+    }
+
+    _getTargets() {
+      const spriteNames = [{ text: "myself", value: "_myself_" }];
+      const targets = Scratch.vm.runtime.targets;
+      for (const target of targets) {
+        if (target.isOriginal && !target.isStage) {
+          const targetName = target.getName();
+          spriteNames.push({
+            text: targetName,
+            value: targetName,
+          });
+        }
+      }
+      return spriteNames;
+    }
+
+    _getTargetFromMenu(targetName, util) {
+      let target = Scratch.vm.runtime.getSpriteTargetByName(targetName);
+      if (targetName === "_myself_") target = util.target;
+      if (targetName === "_stage_") target = runtime.getTargetForStage();
+      return target;
+    }
+  }
+  Scratch.extensions.register(new CollisionTags());
+})(Scratch);