Orzhova, the Church of Deals

{T}: Add {C}.
{3}{W}{B}, {T}: Target player loses 1 life and you gain 1 life.

Sorin's Thirst

Sorin's Thirst deals 2 damage to target creature and you gain 2 life.

Blind Obedience

Extort (Whenever you cast a spell, you may pay {W/B}. If you do, each opponent loses 1 life and you gain that much life.)
Artifacts and creatures your opponents control enter tapped.

Banehound

Impassioned Orator

Whenever another creature you control enters, you gain 1 life.

Swamp

Ajani's Pridemate

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

Gideon's Company

Whenever you gain life, put two +1/+1 counters on Gideon's Company.
{3}{W}: Put a loyalty counter on target Gideon planeswalker.

Plains

Obzedat, Ghost Council

When Obzedat, Ghost Council enters, target opponent loses 2 life and you gain 2 life.
At the beginning of your end step, you may exile Obzedat. If you do, return it to the battlefield under its owner's control at the beginning of your next upkeep. It gains haste.

Toxin Analysis

Target creature gains deathtouch and lifelink until end of turn. Investigate. (Create a Clue token. It's an artifact with "{2}, Sacrifice this artifact: Draw a card.")

Seraph of the Scales

Flying
{W}: Seraph of the Scales gains vigilance until end of turn.
{B}: Seraph of the Scales gains deathtouch until end of turn.
Afterlife 2 (When this creature dies, create two 1/1 white and black Spirit creature tokens with flying.)

Guardian of the Gateless

Flying
Guardian of the Gateless can block any number of creatures.
Whenever Guardian of the Gateless blocks, it gets +1/+1 until end of turn for each creature it's blocking.

Mourning Thrull

({W/B} can be paid with either {W} or {B}.)
Flying
Whenever Mourning Thrull deals damage, you gain that much life.

Karlov of the Ghost Council

Whenever you gain life, put two +1/+1 counters on Karlov of the Ghost Council.
{W}{B}, Remove six +1/+1 counters from Karlov of the Ghost Council: Exile target creature.

Vein Ripper

Flying
Ward—Sacrifice a creature.
Whenever a creature dies, target opponent loses 2 life and you gain 2 life.