Rune-Scarred Helm

Equipped creature has temper. (This creature gets +X/+X, where X is 3 minus the number of cards in your hand.)
When Rune-Scarred Helm becomes attached to a creature that's attacking or blocking, you may discard a card. If you do, draw a card at the beginning of the next turn's upkeep.
Discard a card: Attach Rune-Scarred Helm to a creature you control.