Lifegain relies on small, low-toughness value creatures (Enlightened Confidant, Starscape Cleric, Essence Channeler) to chain life-gain triggers, so extra Meltstrider's Resolve copies let your creatures fight and pick off these fragile engine pieces while buffing your attacker's toughness. Soul-Guide Lantern denies their Case of the Uneaten Feast graveyard recursion plan and strips a card to disrupt their grindy value. Shared Roots is too slow against their proactive lifegain curve, and the second Keen-Eyed Curator is cut since their deck isn't graveyard-dependent enough to need double copies, though the slower grind favors some removal over ramp.