I thought you got hit the way that was closes to the edge of the object that hurt you, i.e. if you're close to the left side of the object then it hits you left. Either way I see nothing wrong with this boss other than it being the same boss again, just like last time and the time before that and even the time before that. You just put a hole in the middle and an extra ball. Sure it might be cheap but that hole should be a non-existant threat anyway, you just keep to one side or something. I also don't see a problem with the lack of a chain. Robotnik got some kind of flashing apparatus on the bottom, I'm guessing that's some form of anti-gravity thing. I think it would be cool if the next boss would expand on that such that Robotnik keeps using the anti-grav-thingymajiggy for new (fresh non-checkered ball) diabolical plans.