Whenever a creature you control attacks, defending player loses 1 life and you gain 1 life.
: Creatures your opponents control block this turn if able, and you choose how those creatures block.
11/24/2014 All blocking declarations must still be legal.
11/24/2014 If there’s a cost associated with having a creature block and you choose for that creature to block, its controller can choose to pay that cost or not. If that player decides to not pay that cost, you must propose a new set of blocking creatures.
11/24/2014 You’ll choose how each creature controlled by an opponent blocks, even if that creature wasn’t on the battlefield or wasn’t controlled by an opponent as the activated ability resolved.
11/24/2014 In a multiplayer game, if more than one player activates Brutal Hordechief’s activated ability on the same turn, the controller of the last ability to resolve will choose how any creatures controlled by players who didn’t resolve this ability will block.
11/24/2014 The defending player affected by Brutal Hordechief’s triggered ability is determined relative to the creature that attacked. For example, if Brutal Hordechief attacked one opponent and two other creatures you control attacked another opponent, the first opponent would lose 1 life and the second opponent would lose 2 life. You’d gain a total of 3 life.