Mewgenics review

If you’ve been thinking about forming a deeply unhealthy relationship with a videogame in 2026, Mewgenics is for you.

‘Obsession’ isn’t a strong enough word to describe my last three weeks with this bizarre roguelike strategy game/cat breeding simulator. Its core loop—taking adventuring parties of feline warriors out to face the dangers of the neighborhood, returning with the spoils (or four dead cats), and managing your household to raise a new generation for the next expedition—has kept me enthralled for 100 hours and counting. And after all that time, I’m still discovering new quests, unlocks, secrets, bosses, builds, diseases, unhinged novelty songs, and more.

(Image credit: Edmund McMillen, Tyler Glaiel)

Each run, you handpick four of the cats currently scurrying around your cluttered little home, and assign them each a familiar D&D-style class—such as fighter, mage, or cleric—which adds new randomised abilities to their character sheet alongside whatever odd gifts they were born with. Then you pick a region to start in—at first just the alleys of your local neighbourhood—and set off across a simple overland map.

Along the way are points of interest like shops and random events (usually decided by a simple stat check), but the meat of each adventure is the fights. Pitting you against an enormous variety of bizarre monsters, these turn-based battles are pleasingly quick and accessible, avoiding the steep learning curve that can plague some roguelikes.

(Image credit: Edmund McMillen, Tyler Glaiel)

You fight across small grids, with simple directional abilities. Each cat has a basic attack inherent to their class—like a hunter’s long-range arrows, or a tank’s knockback punch— which can be used once per turn, as well as a maximum of four different spells limited only by their mana. A maximum of two passive abilities each can add further synergies, and equipment adds its own bonuses, but that’s pretty much it.

That simplicity prevents too much analysis paralysis—you’re only ever dealing with one cat’s turn at a time, and while your choices are meaningful, there’s usually only a few quick ones to make. Enemy abilities add the biggest wrinkle, often dictating your approach to an encounter. A creature that deflects projectiles back at its attacker, for example, demands a very different strategy to one that charges forward every time it takes damage.

(Image credit: Edmund McMillen, Tyler Glaiel)

There’s enough tactical depth there to make each fight engaging, but they’re not deeply intricate puzzles, and it’s far less precise than Into the Breach or even XCOM. Battles are often cluttered, and it can be difficult to read what’s happening at a glance even when using the helpful tactical view. The biggest turning points often come as a result of randomised elements or unpredictable behaviours, and frankly it can often feel unfair, especially when run-derailing enemy abilities, such as instantly killing a cat or infecting it with a debilitating disease, take you by surprise.

But that, really, is where the joy of Mewgenics lives—in the chaos. Fair and precise is not the goal. The goal is to come out of every run with a story.

Me, meowself, and Isaac

(Image credit: Edmund McMillen, Tyler Glaiel)

The game was co-developed by Edmund McMillen, creator of The Binding of Isaac, and despite the shift of genre this feels like the most direct successor yet to that iconic game. It carries forward the same love of randomisation and emergent drama, with countless different elements coming together in every run to create some new combo you’ve never seen before.

As your cats level-up, fall afoul of random events, scrape through fights, earn weird new equipment, and suffer the effects of forbidden magic, your run tilts in strange and fascinating directions.

(Image credit: Edmund McMillen, Tyler Glaiel)

Is it fair when my only healer contracts lycanthropy and keeps turning into a werewolf mid-battle when I need his healing powers most? Or when my most solid frontline fighter becomes permanently uncontrollable because a friendly zombie infected him with distemper? Or when my druid grows menacing mutant eyes that have a chance to make all his allies flee in terror whenever he uses his team-buffing song? No, no, and no—and funny as it often is, it can be genuinely frustrating when things go wrong, especially as runs can easily take an hour or more before suddenly being knocked off wildly off course.

The only sane path forward is embracing the chaos. As I learned more and more to take the rolling nightmare for what it is, I found myself snatching victory from the jaws of defeat, discovering brutal combos that give the game a taste of its own cruel medicine.

(Image credit: Edmund McMillen, Tyler Glaiel)

One run seemed doomed when a ferociously contagious case of ebola spread through my party—but by the end of it, I’d weaponised the disease, using my cleric’s OCD-driven grooming behaviours to manage the symptoms while spreading it to enemies far less equipped to cope. In another, I was able to combo a set of plastic bottles with a chronically incontinent cat to create an endless source of free healing water.

My most hopeless moment yet came when my star cat developed “blood frenzy”, a condition that gave him an extra action every time he got a kill, but made him so uncontrollably insane that he’d soon slaughtered and eaten all his teammates. Surely that’s unrecoverable?

Except… that disorder turned out to be the final piece of a puzzle that enabled a completely unstoppable solo cat build, where repeatedly spawning, killing, and devouring fly minions granted him 20 turns a round and endless healing. I simply watched in delighted horror as he tore the final boss to pieces before it even got to act. The final punchline? One last random event post-adventure cured his blood frenzy just in time to come home acting like nothing happened.

(Image credit: Edmund McMillen, Tyler Glaiel)

You’ve probably got the sense by this point that the game’s tone is as chaotic as its systems. Despite (or perhaps because of), the extensive involvement of collaborator Tyler Glaiel in the game’s development, Mewgenics is another game that feels like peering into the depths of McMillen’s own brain, where evangelical christianity, Magic: The Gathering, body horror, and poop jokes collide.

It doesn’t have the full edgelord humour of The Binding of Isaac, a game that practically falls over itself to tell you dead baby jokes. But it does still feel more inspired by early 2000s South Park episodes and Newgrounds culture than anything in the modern landscape, for better and worse—and the often juvenile approach won’t be for everyone.

But the immature humour certainly represents no lack of seriousness in the game’s design. That’s perhaps most evident in the game’s other half, when you’re back at home between runs.

Herding cats

(Image credit: Edmund McMillen, Tyler Glaiel)

The sheer scale and ambition of the cat breeding system is pretty astonishing. Each of your pets is practically unique, combining an enormous number of possible traits together to determine their appearance, stats, abilities, and even their distinctive voice (drawing from a library of over 12,500 meowing cameos from celebrities, internet personalities, McMillen’s kids, and more). Give them opportunities to mate, and they’ll have kittens who convincingly inherit DNA and learnings from both parents, creating ongoing lineages weaving all through your adventures.

Again here, chaos is the spark that makes Mewgenics come to life. Your control over your cats is deliberately messy and limited—you can place them in different rooms of your house to isolate different groups, and place furniture that influences their behaviour, but ultimately they have minds of their own. They breed with partners you don’t want them to, fight, form relationships, and poop everywhere. Like, everywhere. Your role is not to perfectly control the colony, but to keep nudging things in the right directions, slowly improving your gene pool and making the most of whatever unexpected synergies it throws out.

(Image credit: Edmund McMillen, Tyler Glaiel)

The more you engage with this system, the more layers unfold. Unwanted kittens donated to a local NPC unlock more and more information about the internal lives of your cats, from the stats they’ll pass on to their full family trees to their sexualities. And as cats return from adventures marked by experience and strangeness, elements like mutations, powerful class abilities, and inherited disorders start to trickle down through the generations.

After one of my cats entered a Junji Ito-style crevice and came back a terrifying, stretched out monster, he fathered a whole lineage of bug-eyed half-freaks. Still to this day these glowering monsters take on vital roles in my adventuring parties, taking advantage of their particular… talents.

(Image credit: Edmund McMillen, Tyler Glaiel)

As you produce more and more specialised and high quality cats to take on the terrors of the world, so too does it reveal more and more layers of its own. Starting out in the game’s early hours, simply sending your cats into alleyways and caves, it seems set to be a modest experience, but the more you play, the more new regions and quests reveal themselves.

I’m keen to leave as much unspoiled as possible, because there’s real joy in the way Mewgenics keeps escalating, one-upping itself, and revealing more and more to do, but needless to say your adventures end up taking you to a wide variety of surprising locations filled with an enormous selection of horrible things that want to kill your cats. By the end, it seems quaint and absurd that you started out simply scrapping with tomcats behind dumpsters.

(Image credit: Edmund McMillen, Tyler Glaiel)

Clever non-linear progression makes the most of what’s there, too. Quests to unlock later paths often involve going back to earlier ones with new modifiers and challenges, and each class you unlock can gain new abilities by being taken on a run through old areas. That’s before you even get to a system that allows you to replay parts of the game on harder difficulties and confront more powerful versions of bosses to unlock yet more stuff. It’s built to be fantastically replayable, providing more and more opportunities to crash its different systems together and revel in the results.

And there’s so much that even in 1600 words I haven’t had the chance to get to yet—from roaming bosses that bring the fight right to your house and allow your retired cats one last moment of glory, to the soundtrack by Ridiculon that gives every bossfight its own wonderfully catchy custom song and is sure to take over Spotify next week, to ultra-rare “cryptid” cats, to hilariously horrible side-quests that charge you with carrying malfunctioning inventions through different parts of the game, to countless preposterous stories of my own best, worst, and weirdest runs.

(Image credit: Edmund McMillen, Tyler Glaiel)

It’s an unbelievably dense tapestry for such a silly idea, more so even than The Binding of Isaac before it. I really am not exaggerating when I say that after three weeks and over 100 hours of Mewgenics taking over my personal life, it’s still surprising me every run and there’s an intimidating amount left for me to do and see. I should be burned out on it—instead, I’ll be booting it up for another go the minute I finish this review.

That’s a sign of a truly landmark roguelike, and the most impressive work to date for one of PC gaming’s most iconic indie developers.