Living Destiny

The lifegain here is a tax on information rather than a tax on resources: you pay four mana and reveal a creature. Most lifegain instants meter their output by mana spent, which keeps the ceiling fixed and the cost honest. This one instead reads off a card you already have, which means the spell does nothing about your board, your hand size, or your tempo: it converts a bystander creature's mana value into life and asks you to advertise what you're holding to do it. That reveal is the real cost. Against an opponent reading for a combat trick or a counterspell window, telling them you have a fatty in hand can matter more than the life ever will, and the spell gives you no way to bluff: the creature has to be real and it has to be shown. The payoff scales with the heaviest thing in your hand, so the design quietly pushes toward big-creature decks, the exact decks that would rather be casting that creature than revealing it for a one-shot heal. It is a fringe-rate stabilizer whose most natural homes are the ramp shells full of expensive creatures, where a single reveal can buy a double-digit life swing at instant speed. The friction between "show your best card" and "gain the most life" is the whole design, and it never fully resolves in the spell's favor.