Zerxus isn't exactly fashionable, but his outfit is at least less conspicuous than a full suit of armour. There's nothing he can do about the horns, of course; hopefully the Barge is either making them invisible or convincing people that's definitely just a normal mutation going on.

He wasn't looking for Pyotr specifically, but he is trying to keep an eye on inmates in general; he pivots towards him immediately after that first sweeping glance of the bar, which handily bolsters the assumption. He's successfully thrown off, too, at least for a moment, expression shifting from bafflement to exasperation to . Okay, fine, if they're doing this -

"I'm not much of a player myself, but I'll definitely take that drink." Zerxus manages to sound casual, if not quite cheerful. He's trying not to think about trailing along after Nydas when they were young, arguing with him about cheating but backing him up every time, so obviously he does.

He steals a chair from another table, sliding it close enough to Pyotr that he can pull off a few tricks of his own.