Two plans of action:
1.) We throw it back in the water and take pot shots. It's a good plan but that thing can swim fast and I'm fairly sure Gabriel is the only one with the capacity to hit it from that range.
2.) We wait until it comes close and then hit it with another No-Fly Zone?(Yes I'm calling it that from now on). My health isn't tremendous right now, nor am I the only one. We have to draw it in without allowing it to breath weapon a mass of us or isolate any of us and then swamp the damn thing with actions. In that case I think we should all be hiding in the towers. Sure it'll see us going in but it won't know what floor we're on, that'll help (Somewhat).