Barter in Blood
Avacyn Restored — Uncommon
Sorcery
Barter in Blood rulings:
2012-05-01: The active player chooses which creatures will be sacrificed first, then each other player in turn order does the same. Then all creatures are sacrificed simultaneously.
2012-05-01: If a player controls only one creature, that creature is sacrificed.
2012-05-01: Barter in Blood doesn’t target any creatures and may be cast even if a player controls fewer than two creatures.