Lifegain relies on stacking small lifegain triggers from Hinterland Sanctifier, Amalia Benavides Aguirre, and Case of the Uneaten Feast to grow threats and drain you, so proactive pressure and efficient removal matter more than hand disruption. Preacher of the Schism punishes their small creature base with deathtouch and races well since it draws cards when you have the most life, while M.O.D.O.K.'s static -1/-1 and lifelink both attack their lifegain plan and shrinks their board. Shoot the Sheriff and your existing Requiting Hex answer most of their low-toughness creatures like Deep-Cavern Bat and Starscape Cleric before Amalia can explore repeatedly. Prioritize removing Amalia Benavides Aguirre early since it snowballs if left unchecked.