When Mega Crit released Slay the Spire 2 into Steam Early Access on March 5, the game hit 3 million units sold within a week with more than 25 million runs attempted. Three days after launch, the numbers climbed higher still. Slay the Spire 2 peaked at 575,000 concurrent players, making it one of the largest launches in Steam history.
The scale of that achievement becomes clearer when set against the competition. Balatro peaked at 44,000 concurrent users in January 2025, Slay the Spire 1 at 57,000 in December 2025, and Monster Train 2 at 18,500 shortly after its May 2025 launch. The early access game generated more than 13 times Balatro's peak, and it achieved this while competing against major releases including Bungie's Marathon, Pokemon Pokopia, and the continued popularity of titles like Resident Evil Requiem and Arc Raiders.
Revenue figures tell an equally striking story. By March 19, exactly 14 days after launch, Slay the Spire 2 had sold 4.6 million copies on Steam, grossing over $92 million. This matters because it outpaces two of the most celebrated indie titles in recent memory. Hades II has earned $82 million on Steam over its lifetime, while Hollow Knight: Silksong has earned $83 million. Slay the Spire 2 surpassed both figures in half that time, despite being in Early Access.
What makes this achievement more remarkable is the unusual sales conversion rate. Slay the Spire 2 boasts a high wishlist-to-sales conversion rate of 31% during the debut week, while typically this figure is only around 7-10%. That degree of confidence in a purchase is rare.
Consumer trust as a competitive advantage
Industry analysts attribute much of the success to factors beyond marketing noise. Mega Crit's reputation as a developer likely played a role; its early access wasn't weighed down with microtransaction cruft, season passes, or development scandals, and in a market fatigued by monetisation friction, that is a meaningful conversion driver. The studio charged a straightforward $25 USD for early access with no premium cosmetics or battle passes cluttering the experience.
The publisher said as much in public statements. Developer Casey Yano opened an update with "HOLY MACKEREL," saying that even if he "threw out [his] back from overworking," he remained "quite in high spirits" about the reception. The tone suggests genuine surprise at the scale of player enthusiasm.
Player behaviour supports that assessment. More than half of players have already played over 20 hours, and 1% have played over 100 hours. This is engagement depth, not launch-day spike noise. A game that people abandon after an hour does not see half its player base reach the 20-hour mark.
The competing narrative: market saturation and genre fatigue
The opposing view deserves serious consideration. The deckbuilder roguelike genre has exploded since the original Slay the Spire launched in 2017. Since 2017, the genre became phenomenally busy, with ten thousand copycats and many other fantastic games clearly very inspired by Mega Crit's design; it's fair to say that without Slay the Spire, you don't get Balatro, Monster Train, Griftlands or the other seven examples. By that logic, the market should be saturated, and Slay the Spire 2 should cannibalize those titles rather than transcend them.
Yet the data suggests otherwise. Roguelikes generated around $400 million in Steam revenue in 2025, up 80% from 2024, which was also a record for the genre; thanks to the Q1 launches of Mewgenics and now Slay the Spire 2, roguelikes are on track to reach new revenue heights this year. Rather than shrinking the pie, Slay the Spire 2 appears to have expanded it.
One further consideration: the substantial revenue from Slay the Spire 2 is partly due to the game's popularity in China. Chinese players account for over a third of Slay the Spire 2's audience, and China was also pivotal for the original Slay the Spire. This suggests that much of the audience was not directly accessible to Western marketing, but found the game through other channels. An indie studio with limited advertising budget could never have engineered that reach. The audience chose them.
The pragmatic takeaway
Slay the Spire 2's success reflects something worth noting in a market increasingly shaped by corporate consolidation and AAA bloat. Roguelikes pull in player counts that rival, and in some cases exceed, major AAA launches; a two-person indie studio producing a game that outperforms a Bungie shooter on day one is a significant data point for where player interest currently sits.
That does not mean indie games always outperform AAA titles, or that bigger budgets do not matter. But Slay the Spire 2 demonstrates that consumer restraint, honest design, and seven years of player goodwill can compete effectively even in a crowded market. The game won because it did what a sequel should: took the original, improved it, and did not get in the players' way.
As the game moves through its Early Access period, expect the numbers to shift. Bugs will emerge, balance patches will displease some players, and casual interest will plateau. But the underlying fact remains: millions of people wanted more Slay the Spire, and when offered a straightforward, well-made path to that experience, they paid. That is a business model that should survive longer than the flavour-of-the-month games built on hype.