Porphyry Nodes

Oracle Text

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.

Card Rulings

7/15/2006 This card’s ability is not targeted, so even untargetable creatures or those with Protection can be chosen.
2/1/2007 This is the timeshifted version of Drop of Honey.
7/1/2013 If the creature with the least power has indestructible, the ability does nothing.
7/1/2013 If there are multiple creatures tied for least power and some but not all of them have indestructible, the ones with indestructible can’t be chosen.