Mewgenics Review – Edmund McMillen’s Cat Breeding RPG Is Purrfect Chaos

Thirteen years. That is how long Mewgenics spent in development hell before Edmund McMillen and Tyler Glaiel finally shipped it. The game was announced in 2012, shelved, restarted, shelved again, and resurrected multiple times before quietly launching on Steam in February 2026. It recouped its entire development budget in three hours. It sold one million copies in its first week. It sits at a 90 on Metacritic, a 90 on OpenCritic with a 96% recommendation rate, and a 95% Overwhelmingly Positive rating on Steam. Here is our verdict on whether Mewgenics is worth your time and money.

The answer is yes. This is the highest-rated game of 2026 so far, and it earns that distinction. For background on the game’s tortured development journey, see our Mewgenics launch coverage.

What Even Is Mewgenics?

Explaining Mewgenics is part of the challenge. On the surface, it is a cat breeding roguelite RPG. You collect cats, breed them, raise them, and send them into procedurally generated dungeons. But that description misses what makes the game extraordinary: the depth of its systems and the absurdity of their interactions.

Each cat has a procedurally generated genome that determines its appearance, stats, personality traits, and hidden abilities. Breeding two cats together produces offspring with combined and mutated traits. Some mutations are cosmetic. Others fundamentally change how a cat fights, explores, or interacts with the world. There are over 100 distinct trait categories, and they stack, conflict, and combine in ways that produce genuinely surprising emergent behavior.

You might breed a cat with acid spit that also happens to be narcoleptic and afraid of water. That cat is useless in sewer dungeons but devastating in desert biomes. This kind of systemic depth means no two runs feel the same, and the breeding metagame alone could consume dozens of hours before you even engage seriously with the dungeon content.

The Dungeon Loop Is Deceptively Deep

Dungeons in Mewgenics are procedurally generated, room-by-room gauntlets that combine real-time combat with environmental puzzle-solving. Your party of cats fights autonomously based on their personality traits, but you influence their behavior through positioning, item usage, and environmental manipulation. It feels like a real-time tactics game wearing a cute indie skin.

The difficulty curve is deliberately steep. Early dungeons lull you into complacency with manageable enemies and generous loot drops. Mid-game introduces mechanics that punish carelessness: permadeath for cats, environmental hazards that exploit specific trait weaknesses, and boss encounters that require specific breed compositions to survive. Late-game content is brutally challenging and requires extensive breeding optimization to clear consistently.

McMillen’s design philosophy from The Binding of Isaac is clearly visible here. Runs are meant to end in failure. Each failure teaches you something about the breeding system, the trait interactions, or the dungeon mechanics. Progress is measured not just in dungeon completion but in the quality and depth of your cattery. The 200-plus hours to “beat” the game and the 500-plus hours to reach 100% completion are not padding. They reflect the genuine depth of systems that keep revealing new layers the longer you play.

Presentation and the McMillen Touch

Visually, Mewgenics is unmistakably an Edmund McMillen game. The art style blends cute and grotesque in a way that only McMillen can pull off. Cats range from adorable to horrifying depending on their mutations, and the dungeon environments shift between whimsical and disturbing. The soundtrack is excellent, with dynamic music that responds to combat intensity and exploration state.

The humor is dry, dark, and ever-present. Item descriptions, cat trait names, and environmental storytelling all carry McMillen’s signature absurdist tone. If you enjoyed The Binding of Isaac’s aesthetic, you will feel right at home. If you found it off-putting, Mewgenics is slightly less aggressive in its grossness but still firmly in that territory.

The Must-Play Badge

We do not use the “Must-Play” designation lightly. Mewgenics earns it. At $29.99, you are getting a game with more content depth than titles charging twice the price. The breeding system alone is one of the most innovative mechanics we have seen in years. The dungeon loop is satisfying from hour one through hour two hundred. The procedural generation ensures that no two playthroughs are identical in any meaningful way.

The fact that it is Steam Deck Verified from day one is the cherry on top. This is the kind of game that was made for handheld sessions: pick it up for 20 minutes of breeding, sink into a two-hour dungeon run, or spend an evening optimizing your cattery for a specific late-game challenge. The flexibility of play styles is remarkable.

Known Issues at Launch

Mewgenics is not flawless. There are some genuine technical issues that need patching. Controller users have reported intermittent input bugs where button presses fail to register during menu navigation. Some players have experienced loading hangs when transitioning between the overworld and certain dungeon biomes, requiring a game restart. And there is a known item duplication glitch involving the breeding menu that McMillen has acknowledged and promised to fix in the first major patch.

None of these issues are game-breaking for most players, but they are worth noting. The loading hang in particular can cost you unsaved breeding progress if it occurs at a bad time. Save frequently until the patch lands.

A Triumph 13 Years in the Making

Mewgenics is the rare game that justifies its extended development timeline. Every system feels intentional, every mechanic feels polished, and the depth of content is staggering. It is simultaneously the best roguelite of 2026, the best indie game of 2026, and a strong contender for overall game of the year. At $29.99 with hundreds of hours of content, it is one of the best value propositions in gaming right now.