First printed in War of the Spark (2019)
Creature — Merfolk Mutant
Flying
When this creature enters, put a +1/+1 counter on target creature you control.
: Proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)
1/1
- Illustrated by
- Sara Winters
Legality
- Legal in
- Pioneer, Modern, Legacy, Vintage, Historic, Timeless, Penny Dreadful, Gladiator, Commander, Duel Commander, Tiny Leaders, Oathbreaker, Brawl, Competitive Brawl
- Not legal in
- Standard, Pauper, Future Standard, Alchemy, Premodern, Old School 93/94, Pauper Commander, PreDH, Standard Brawl
Rulings (7)
- You may choose Merfolk Skydiver as the target of its own ability.
- To proliferate, you can choose any permanent that has a counter, including ones controlled by opponents. You can choose any player who has a counter, including opponents. You can't choose cards in any zone other than the battlefield, even if they have counters on them.
- If a player or permanent has more than one kind of counter on it, and you choose for it to get additional counters, it must get one of each kind of counter it already has. You can't have it get just one kind of counter it already has and not the others.
- You don't have to choose every permanent or player that has a counter, only the ones you want to add another counter to. Since "any number" includes zero, you don't have to choose any permanents at all, and you don't have to choose any players at all.
- If a permanent ever has both +1/+1 counters and -1/-1 counters on it at the same time, they're removed in pairs as a state-based action so that the permanent has only one of those kinds of counters on it.
- An ability that triggers "Whenever you proliferate" triggers even if you chose no permanents or players while doing so.
- Players can respond to a spell or ability whose effect includes proliferating. Once that spell or ability starts to resolve, however, and its controller chooses which permanents and players will get new counters, it's too late for anyone to respond.
Prices
MTGO price: 0.003 TIX, the cheapest non-foil print (average sell price on GoatBots, 30 Oct 2026).
Combos
8 combos, the most popular first:
- Infinite turns, Lock: Magistrate's Scepter + Merfolk Skydiver
- Infinite turns, Lock: Living Plane + Magosi, the Waterveil + Merfolk Skydiver + The Ozolith
- Infinite turns, Lock: Kamahl, Heart of Krosa + Magosi, the Waterveil + Merfolk Skydiver + The Ozolith
- Infinite turns, Lock: Magosi, the Waterveil + Merfolk Skydiver + Nature's Revolt + The Ozolith
- Infinite turns, Lock: Destiny Spinner + Magosi, the Waterveil + Merfolk Skydiver + The Ozolith
- Infinite turns, Lock: Magosi, the Waterveil + Merfolk Skydiver + Natural Emergence + The Ozolith
- Infinite turns, Lock: Merfolk Skydiver + The Legend of Kuruk // Avatar Kuruk + The Mighty Thor, Jane Foster
- Infinite turns, Lock: Baboon Spirit + Merfolk Skydiver + The Legend of Kuruk // Avatar Kuruk