Take it from a long-time Dungeon Master and RPG player. When you have something big and monstrous like this? It goes down hard and it goes down swinging. Nobody's getting out of this fight without any injuries.
Heck, you never know, someone might die on this very first fight. Never forget the risks.
But I'm thinking that right now, we're doing a round of actions back and forth - and by the end of the week, the thing's gonna be dead. The only difference is probably going to be how beat up the rest of us are gonna be. Besides, playing out a long, gruelling fight is fun times.