Mewgenics Hits Number One on Steam After 14 Years in the Making
Edmund McMillen's cat breeding tactics roguelite sold over 152,000 copies in its first three hours and became the first must-play game of 2026.
Edmund McMillen’s long awaited cat breeding roguelite Mewgenics launched on Steam yesterday and immediately took the number one best seller spot. The game sold over 152,000 copies within its first three hours, more than tripling the launch numbers of The Binding of Isaac: Rebirth.
McMillen confirmed the game had already recouped its entire development budget within those same three hours.
14 Years From Announcement to Launch
Mewgenics was originally announced in 2012 as a collaboration between McMillen and Tyler Glaiel. The project went through multiple cancellations, restarts, and complete redesigns before finally reaching players on February 10, 2026. That patience paid off. The game hit a peak of 65,893 concurrent players on launch day according to SteamDB.
What Exactly Is Mewgenics?
Picture XCOM’s tactical grid combat crossed with Pokemon’s breeding mechanics, all wrapped in McMillen’s signature dark humor. You breed cats with unique genetic traits, send them into turn based tactical battles on procedurally generated grids, and then retire the survivors to breed the next generation.
The twist is that your cats permanently retire after each successful run. Their kittens inherit abilities, spells, and genetic conditions from both parents. You are constantly building new squads from the offspring of your previous heroes.
The numbers are staggering. Over 1,000 unique abilities spread across 10+ character classes. More than 900 items and 200 enemies. The main campaign clocks in at over 200 hours.
Critics and Players Agree
Mewgenics became the first game of 2026 to earn “Must Play” status on OpenCritic, reaching a Top Critic Average of 90 with 94% of critics recommending it. Steam reviews sit at Overwhelmingly Positive with 96% approval from nearly 4,000 reviews.
IGN called it “one of the most nuanced and thoughtful strategy games.” Players praise the depth of the breeding system, the tactical combat, and the sheer amount of content packed into the game.
Should You Play It?
If you have any fondness for tactical roguelites, this is an easy recommendation. The genetic breeding system adds a layer of long term strategy that most games in the genre lack entirely. Every run feeds into the next through your cat lineage. And yes, you can pet the cats.
Mewgenics is available now on Steam for $39.99 with a 10% launch discount running until February 24.
Want to know what makes McMillen tick? Read our deep dive into what every indie dev can learn from Edmund McMillen.
