Have

Ajani's Pridemate

Whenever you gain life, put a +1/+1 counter on Ajani's Pridemate.

Marauding Blight-Priest

Whenever you gain life, each opponent loses 1 life.

Dire Tactics

Exile target creature. If you don't control a Human, you lose life equal to that creature's toughness.

Plains

Caves of Koilos

{T}: Add {C}.
{T}: Add {W} or {B}. Caves of Koilos deals 1 damage to you.

Vona, Butcher of Magan

Vigilance, lifelink
{T}, Pay 7 life: Destroy target nonland permanent. Activate only during your turn.

Soul Warden

Whenever another creature enters, you gain 1 life.

Cliffhaven Vampire

Flying
Whenever you gain life, each opponent loses 1 life.

Swamp

Elas il-Kor, Sadistic Pilgrim

Deathtouch
Whenever another creature you control enters, you gain 1 life.
Whenever another creature you control dies, each opponent loses 1 life.

Markov Purifier

Lifelink
At the beginning of your end step, if you gained life this turn, you may pay {2}. If you do, draw a card.

Vault of the Archangel

{T}: Add {C}.
{2}{W}{B}, {T}: Creatures you control gain deathtouch and lifelink until end of turn.

Phyrexian Missionary

Kicker {1}{B} (You may pay an additional {1}{B} as you cast this spell.)
Lifelink
When Phyrexian Missionary enters, if it was kicked, return target creature card from your graveyard to your hand.