Outpost Siege is a rare Enchantment card from Pioneer Masters (PIO), collector number 150.
As this enchantment enters, choose Khans or Dragons. • Khans — At the beginning of your upkeep, exile the top card of your library. Until end of turn, you may play that card. • Dragons — Whenever a creature you control leaves the battlefield, this enchantment deals 1 damage to any target.