Geas of Warfare

Creatures you control get +2/+0 and have
Trample and Haste. At the end of your turn,
if you didn't attack with a creature, Sacrifice
Geas of Warfare.
When Geas of Warfare leave the battlefield,
you lose half your life, rounded up.

"On my name i swear that as long as my enemydraw breath, my blade shall know no rest."
— Geas of Warfare.