Reward the Faithful

Lifegain scaled to your biggest permanent is a strange tap to put on a one-mana instant: the spell does nothing on an empty board and everything once you have resolved a fatty, which is precisely backwards from how most lifegain wants to be drawn. That inversion is the design idea. It belongs to an era obsessed with enormous casting costs (the storm payoffs, the cycling beasts, the giants you ramped toward), so a spell that reads the largest permanent you control was written for a board where that number is genuinely big. The "any number of target players" clause is the second wrinkle, and the one that has aged into relevance: the spell can hand life to opponents as readily as to yourself, which is not generosity but a deckbuilding hook. A card that gives everyone life on command is a liability in most contexts and an engine in the narrow set of builds that punish lifegain or treat life-total swings as a resource. Outside those, it is a Healing Salve with a towering ceiling and a hard floor, dependent entirely on what you have already committed to the table. The honest read is that it was built as an answer to aggressive starts in an environment where ramping into something huge was the plan anyway, and its enduring identity is that conditional scaling rather than the rate.