David's Gambit

Target creature you control gets +3/+0 until end of turn and deals damage equal to its power to a creature with the greatest power among creatures target opponent controls. If a creature dealt damage this way dies, other creatures controlled by the same player can't block this turn.
"Let no one lose heart on account of this Philistine; your servant will go and fight him."
-David to Saul, 1 Samuel 17:32