Whenever a creature enters, if there are two or more other creatures on the battlefield, exile that creature. Return that card to the battlefield under its owner's control when Portcullis leaves the battlefield.
Untap all creatures you control and all creatures target opponent controls. You and that opponent each gain control of all creatures the other controls until end of turn. Those creatures gain haste until end of turn.
Crovax the Cursed enters with four +1/+1 counters on it.At the beginning of your upkeep, you may sacrifice a creature. If you do, put a +1/+1 counter on Crovax. If you don't, remove a +1/+1 counter from Crovax.: Crovax gains flying until end of turn.
Whenever a nontoken permanent is put into your graveyard from the battlefield, Jinxed Ring deals 1 damage to you.Sacrifice a creature: Target opponent gains control of Jinxed Ring. (This effect lasts indefinitely.)
Spike Feeder enters with two +1/+1 counters on it., Remove a +1/+1 counter from Spike Feeder: Put a +1/+1 counter on target creature.Remove a +1/+1 counter from Spike Feeder: You gain 2 life.
If you would draw a card, you may put a study counter on Pursuit of Knowledge instead.Remove three study counters from Pursuit of Knowledge, Sacrifice Pursuit of Knowledge: Draw seven cards.
