Some questions about the game

So i wanted to evolve my delta phantump into a delta trevenant however the witchdoctor says i need it to hold an item to evolve it i want to know what that item is also i was watching a lp by herovoltsy and i noticed the delta munchlax he got from the mystery gift was holding a hydreigonite but the one i received had no items to speak of so what’s going on with the mystery gift.

Did you try looking at the wiki?

munchlax is not meant to hold a megastone herovoltsy got one thats bugged

ohh ok thank you