Super Greed is a tougher version of Greed and functions as a mini-boss. He can be randomly found inside of a shop or a secret room, but only if Greed has already been encountered this way. Compared to his weaker version, he has pennies for eyes, a dollar sign on his head, and an angrier look. Once Super Greed is encountered in a shop or secret room, he and Greed cannot be encountered that way for the rest of the run.
Shops and secret rooms Super Greed generates in count as miniboss rooms, and cannot be bombed out of. They also prevent any other miniboss rooms from generating that floor.
If Isaac teleports out of the room after defeating Super Greed but without killing any of the Keepers he spawns, Isaac can re-fight Super Greed for extra coins.