Ray Fillet, Man Ray

The Mutagen subgame is what makes this work in TMT, because the format gives the +1/+1 counter time to mean something. Medium speed, medium removal density, and a common toughness map clustered at 2/3 and 3/2 means a 3/3 flier already clears the air over the ground threats that would race it, and the engine accrues from there: the Mutagen lands a counter a turn after Ray does, then the draw ability converts that counter back into a card, shrinking Ray to a 3/3 in the process. You are trading body size for velocity, one card at a time, on a clock the ground can't easily answer.

GU Counters wants it most, P1P3 to P1P5 maindeck: the deck is already running counter-generators, so the Mutagen becomes one more fuel source for a draw outlet that doesn't need a second creature to spin. The Bant legendary shell the uncommon signposts are pushing takes it slightly lower (P1P5 to P1P7), because white's half of that pair leans on equipment-and-go tempo and would rather not spend turn four on an engine that pays off next turn. UR Sneak is the real demotion. It can cast Ray on rate but wants its four-drop to close, and a 3/3 entering a two-turn loop doesn't threaten lethal fast enough to earn the slot.

The pressure point is the sorcery-speed restriction on the Mutagen. Against Stomped by the Foot or Grounded for Life on the crack-back, Ray often eats removal before the counter ever lands, and the engine never starts. That keeps the pick band below the Turtle mythics rather than alongside them. Maindeck in any blue deck regardless: a four-mana 3/3 flier with a built-in token and a draw outlet is a rate you run even when the counters axis is thin.

The +1/+1 counters lineage in Simic and Bant has wanted a self-contained draw engine for a long time, and this fills the slot for two commanders in particular. The cleanest fit is Pir, Imaginative Rascal partnered with Toothy, Imaginary Friend: the Mutagen places a counter (doubled by Pir), and the draw outlet pulls counters off Toothy to refill while still banking the extra card from Toothy's own size-change trigger. Ezuri, Claw of Progress is the other natural home, where the parked counters fuel the experience-fed army and the draw ability turns a glut of counters into cards. Worth noting there: the Mutagen is an artifact, so making it does not give Ezuri an experience counter; only the creature it eventually buffs matters to that engine. The body flies, which matters less than the loop.

This is a Bracket 2-3 counters deck card. The engine wants a turn cycle to convert, since the Mutagen activates at sorcery speed, so it rewards an early deploy and punishes treating it as a finisher. That is the casual tempo where it shines and the high-power tempo where it does not. cEDH has no use for a four-mana value engine that needs two turns to pay off; the draw slot there is already spoken for.

The in-archetype comparison is Ozolith, the Shattered Spire and the proliferate package. Ray Fillet is the better standalone piece because it brings its own counter and its own draw, where Ozolith needs external counter sources to spin. It is the worse piece in a deck already overflowing with counters, since the single Mutagen counter is redundant fuel. In a built-out Pir and Toothy list the two coexist comfortably.

Expect a sub-$5 secondary price as a recent printing. Invisible outside counters-matter shells, which is most of the table.

A four-mana flier with a self-contained draw engine that, in Modern, has no deck asking for it. The counters-matter shells the design points toward (Hardened Scales, modular aggro) want their four-drops to close games faster than a 3/3 that needs a full turn cycle to convert a single counter into a card. Legal but yet to register in tracked play, and there is no archetype currently building toward it. Cut for any threat that pressures the board on the turn it lands.

Legal since its March 2026 printing, but yet to register in tracked Standard play this season. The structural problem is that the engine never finds a shell that wants it. The self-priming loop is real (the Mutagen makes a counter, the draw ability eats the counter for a card), but it converts at a glacial pace: a sorcery-speed token that takes a turn to crack, then two mana per card off a single parked counter. That is a fine value tail in a counters deck, except the counters decks Standard actually fields want their four-drops to close games or stabilize, not to chip one card every other turn. A 3/3 flier for four that loops itself for value is a midrange luxury, and the format's blue midrange has faster ways to draw and harder bodies to deploy.

It also competes for a slot with cards that do the counter-payoff work without asking for setup. Underneath the cross-brand framing, this is a slow engine in a format that has not slowed down enough to run one. A dedicated +1/+1 counters deck with proliferate would change the math, and Standard's pool turns over often enough that a future payoff could hand it a home.

The card stays legal through the fall 2026 rotation and into 2027, with its exact rotation tied to its parent block's schedule. Nothing on the announced pool builds the counters shell it would need, so the read for now is structural: a clean engine waiting on an archetype that does not yet exist.

A four-mana flier that wants a Pioneer +1/+1 counters shell the format has never actually produced. The card primes itself fine: the Mutagen counter feeds the draw outlet without a second creature, exactly as designed. The problem is that four mana for a 3/3 self-contained engine asks the format to slow down when nothing in Pioneer's blue lists wants to. Legal, but yet to register in tracked tournament play. If a Simic or Bant counters deck ever coheres, this is a fringe consideration rather than a payoff the deck is built around.

A four-mana 3/3 flier with a draw engine attached, in a format where Ancestral Recall draws three for one and Black Lotus pays for it on turn zero. The Mutagen loop converts a card every turn cycle at two mana plus a counter, which is glacial against the Power Nine's velocity, and the sorcery-speed restriction means there is no flash finish to justify the body. Force of Will answers it for free if anyone bothers. Vintage has no counters-matter shell asking for this. Legal, but yet to register in tracked tournament play this season. Noise.

A four-mana 3/3 flier whose payoff is a deferred, sorcery-speed card-draw loop. Legacy's blue decks measure card advantage against cantrips that cost one: Brainstorm, Ponder, Preordain. Spending four mana and a full turn cycle to convert a token into a single card is a different category of slow, and the format does not have a counters-matter shell competing at this tier. At four mana it pays the Force of Will tax going in and gets nothing free on the way. The body is an evasive clock, but a 3/3 flier for four is not a clock Legacy cares about when Murktide Regent and Dragon's Rage Channeler set the rate. Legal, but yet to register in tracked tournament play. Does not clear the bar.