Kyrii will check in at HQ to see if he's needed anywhere. But from there will seek out people who need help at targeted locations or run around the City on a kill-spree of the Null. It's really what he's made for and good at.

There's a solid chance he'll get the crap beat out of him at some point and he'll retreat to the clinic right up until it's destroyed. From there he'll keep running around in whatever state he's in. Probably not a death, but he'll be looking pretty rough by the end of all this.

He does have a small charge on his graviton beam emitter that can be used to take out a good sized horde, probably toward the end of the invasion when things are looking bad. Let me know if anyone wants to be around when it goes off!