Honestly, I can’t even see what is really going on in your original screen shots because they aren’t image links so zooming in just blurs things. But basically the “cast to weapon” needs to be a specific instance of the weapon object that you will then call the “fire gun” event on. If you check out video #1 and #25 in the link I provided above I go over casting and how to create references (the thing you need for the object pin of a cast node). If you use an overlap event to pick up the weapon, the overlapped actor would suffice for the object pin. If not, perhaps the references video will give you some idea of how to get the necessary reference for the cast node. You don’t need a “gun” variable.