A-Haywire Mite

The A- prefix marks the Arena rebalance, and the change is quieter than it looks: the life gain on death ticks up from two to three. Everything else stays intact, because the shape was already the point. This is a one-mana colorless artifact creature that answers a noncreature artifact or enchantment by feeding itself to the graveyard: a single-use, instant-speed exile that costs a green pip and the body itself. The sacrifice is what makes the answer work, so the death trigger is not incidental. Trading a 1/2 for a problem permanent while banking three life turns what would be pure card-and-tempo loss into a small refund, a way to soften the fact that you spent a whole creature to deal with an enchantment. That is the logic the rebalance was tuning: not the interaction itself, which is a modular disenchant stapled to a cheap colorless body that any deck touching green can activate, but exactly how much you get paid for the trade. Bumping the life gain by one is the kind of adjustment that never touches how a card plays and only touches how it feels: a marginal sweetener for a card whose real job (cheap, splashable, self-sacrificing artifact and enchantment removal) was already dialed in. The whole rebalance lives in that one extra point of life, which tells you the paper version was very close to right.