Sun Droplet

Lifegain that exists only in proportion to the punishment you've already taken: the counters don't accumulate on their own, they're a ledger of damage dealt to you, paid back one point at a time. That conditional is the whole design. A clock that never gets hit charges nothing, so the artifact is dead weight against an opponent who ignores you and live only against the kind of fast aggression that fills it up. The drip-feed payback carries the rest of the balancing act: you bank the damage all at once but redeem it slowly, one counter per upkeep, which means it pays out on every player's turn rather than once per turn cycle. In a duel that doubles the rate; at a multiplayer table it scales with the number of upkeeps that come around, so a burst of twelve face damage becomes a long trickle that buys turns rather than erasing the hit. It rewards being attacked, then makes you wait to be repaid. That puts it in a small family of artifacts that turn an opponent's offense into a resource, and it sits at the patient end of that family, less a wall than a tax on the aggressor's tempo. Two generic mana imposes no color commitment, which lets it slot anywhere, but the payoff is always backloaded and always contingent on actually getting hurt. Designing lifegain that pays out only after you've taken the damage is a strange axis to build on, and it keeps the card defined by the matchup it's built to survive rather than by anything it does on its own.