Sanguine Bond

Whenever you gain life, target opponent loses that much life.

Swamp

Anguished Unmaking

Exile target nonland permanent. You lose 3 life.

Hellish Rebuke

Until end of turn, permanents your opponents control gain "When this permanent deals damage to the player who cast Hellish Rebuke, sacrifice this permanent. You lose 2 life."

Fell the Mighty

Destroy all creatures with power greater than target creature's power.

Plains

Rashel, Fist of Torm

Double strike
Auras you control have exalted. (Whenever a creature you control attacks alone, it gets +1/+1 until end of turn for each instance of exalted among permanents you control.)

Astarion, the Decadent

Deathtouch, lifelink
At the beginning of your end step, choose one —
• Feed — Target opponent loses life equal to the amount of life they lost this turn.
• Friends — You gain life equal to the amount of life you gained this turn.