Speed is Genos's greatest strength outside his lasers. It's a heavy nerf, but even then, they can't dodge his beams and even if they could, his strongest ones are around town level so the radius is large. I'd still give it to Genos but I'd say the kage would have a shot. The key people are Onoki for his scale of attacks and hax, and Tsunade for healing and probably being the only one strong enough to harm him with melee. If Genos takes one of them out early it's his win for the taking.