Re: OOC! Leon came with James Barlow. He might've been a little standoffish at first, but after getting a few drinks in him he'd have become pretty outgoing and chatted with people/probably got a little handsy with James.
Tasslehoff also showed up. He had no concept of Halloween costumes beforehand, but he might have "found" bits and pieces or costumes at the party to make some sort of creative mashup (feel free to call him out if he "fround" bits from your costume to incorporate). He'd have tried to talk to probably everyone, possibly told spooky stories from back home about how he's spoken with ancient forest ghosts and Death Knights. Was delighted with literally everything.