Mercer, Rage of the Storm

+2: Mercer, Rage of the Storm deals 2 damage to target player. If the total damage dealt this way equals 25 or more, that player loses the game.
-5: Mercer, Rage of the Storm deals 5 damage to target player, and every creature they control; you gain life equal to the damage dealt this way.
-20: You get an emblem with "Damage dealt from sources you control give you life equal to the damage dealt, and deal Wither damage."