Sigma, Master of Gravity

Accretion — {1}{u},{t}: Target creature becomes tapped and takes damage equal to Sigma's power. Put a gravity counter on Sigma.
Kinetic Grasp — {1}{u}{u}: Counter target spell that targets you or a permanent you control. Put a gravity counter on Sigma.
Gravitic Flux — {2}{u}{u}{u},{t}: X target creatures become tapped and take X damage, where X is the number of gravity counters on Sigma. Remove all gravity counters from Sigma.