Aaron, Realities Doom

This spell can't be countered.
ETB - When Aaron, Realities Doom enters the battlefield, collect all other nonland permanents
into a stack, shuffle the stack, and distribute the
cards facedown evenly among all players. Each
player takes damage equal to the total CMC of all
cards they received and gains control of their
stack. Discrepancies on distribution are left to the controller of Aaron, Realities Doom.