How about this- we act all friendly to earn his trust and think we're his friends (he definitely doesn't have any so he'll be gullible), then we invite him to DST server and play together. When he goes afk we build grass walls around him and once he's back we SET EVERYTHING ON FIRE AND WATCH HIM BURRRRN, LOOK AT HIS FLESH TURN RED AND SLOWLY DARKEN, HIS EYEBALLS MELTING OUT OF SCHOOL, HIS AGONIZING SCREAMS FILLING THE AIR!
And then we steal all the stuff he had on him that didn't turn to ashes, ban him out of the server and continue playing like nothing ever happened.