Peter started to laugh, because it was so ridiculous that he didn't know what else to do. "There's a bloody mountain troll in the freaking school. I think that needs to be reiterating." Not that they could forget. The bubble kept him prisoner, but it didn't stop the screaming, which got louder as he tried to get out.
"We could leave him right here, and go find Remus. I mean, it's his thing, yes? Department of Magical beasts and whatever the new name is." Peter couldn't keep track of all the name changes and in the end, he didn't think names were as important as politicians assumed they were. People didn't care about the names, but what you did.
"We could send a patronus to Harry and Ron, let them know." This was going to be a major problem. Not so much stopping the troll, because they were pretty stupid and the bubble would hold, but because they had no idea what to do with it. "I wonder what's happened to all the different troll communities with no wizards to train them. Are there any self sufficient ones? This really seems like a Remus question."