Porphyry Nodes
21a8f0e5-8fec-45b2-a6a0-59d7b493a259
$2.07 CND
At the beginning of your upkeep, destroy the creature with the least power. It can't be regenerated. If two or more creatures are tied for least power, you choose one of them.
When there are no creatures on the battlefield, sacrifice Porphyry Nodes.