I kind of like it, however, the unupped cost should be 1 lower. Or up the upped cost by 1.
I can imagin two uses for this creature: one in a life stall and one in an OTK (chimera-antimatter) deck. Considering how easy it is to spam this creature (via mitosis and fractal), the healing it gives may be slightly too much; I'd lower it to 4.
Correct me if I'm wrong, but there seems to be two abilities: one that heals you, and one that increases its damage. Which is active, and which is passive? Or is it like Steam Machine, where one active ability controls both the damage pump and the damage decrease?