Shriv Dragon

{u}{u} Exile a creature you control, the opponet loses life equal to that creatures toughness or strength, whichever one is higher.
{t}{u}{u} Sacrifice Shriv Dragon: All creatures you controll get +2/+1
{t}{u}{u} Sacrifice Shriv Dragon: All creatures you control get +5/+4, First Strike, and Double Strike until ene of you next turn.