Swamp

Ephemerate

Exile target creature you control, then return it to the battlefield under its owner's control.
Rebound (If you cast this spell from your hand, exile it as it resolves. At the beginning of your next upkeep, you may cast this card from exile without paying its mana cost.)

Soul Warden

Whenever another creature enters, you gain 1 life.

Marauding Blight-Priest

Whenever you gain life, each opponent loses 1 life.

Harsh Sustenance

Harsh Sustenance deals X damage to any target and you gain X life, where X is the number of creatures you control.

Soul's Attendant

Whenever another creature enters, you may gain 1 life.

Cloudshift

Exile target creature you control, then return that card to the battlefield under your control.

Plains

Suture Priest

Whenever another creature you control enters, you may gain 1 life.
Whenever a creature an opponent controls enters, you may have that player lose 1 life.

Mordor Muster

You draw a card and you lose 1 life.
Amass Orcs 1. (Put a +1/+1 counter on an Army you control. It's also an Orc. If you don't control an Army, create a 0/0 black Orc Army creature token first.)