MARTY'S LOKI went as Allison's "date". It's not really a date. He just wanted to be a nuisance to somebody. Shortly after arriving he promptly snatches himself a bottle of (damn that looks expensive) champagne, ditches Allison, and perches himself on a whiskey barrel on the outskirts of the party center, where he stares off towards the dark woodlands outside of Escalante, only briefly listening to what's going on at the party. Kind of weird for Loki not to be social. Hmm.
ORLIN attended, but he's not happy. Far from it in fact. He's downright depressed about the situation with Dolores. He'll be milling around the drinks table looking very sad and pathetic.
OBI-WAN arrived with Leia. They were already in the area. He's suspicious, but he doesn't know why. He will make casual chitchat with anyone who approaches him. But mostly he's keeping an eye out for Leia to make sure she's safe.
SPOCK attended for scientific purposes only. He's in observation and data collection mode.