Yuren, Loyal Rune-Mage

+2: Create a Runestone Artifact with "Equipped creature gets +1/+1." Then Equip it to target creature.
-1: Destroy all Runestone Artifacts. You gain X life where X is the number of Runestones sacrificed.
-3: Creatures you control get +2/+2 and Indestructible untill the end of your turn.