Mercutio has probably been mildly dragged into this by Dionysus -- it would not normally occur to him to act, of all things; but it sounded entertaining enough. When he enters the room, he gives a little bow towards those assembled -- he only really knows two of them, so it's only polite.

"I do not know the material well," he says with a slight shrug. "So I do not really have any preference for a role, but this sounded like it might be fun." He picks one of Puck's monologues from A Midsummer Night's Dream, again, a suggestion from Dionysus. He's got it mostly memorized, having taken the time to do so in lieu of wandering around the mansion looking for ways to harass people. He did need a slight explanation of the story, but his cold read is passable enough. For the talent portion, he of course chooses swordplay, and it is clearly evident that this is one thing at which he is very good. Perhaps not up to Laertes' standards, but he can certainly hold his own with a sword.