Deltarune launches to 12,865% more Steam players than Undertale had on day one, becoming the top-selling game on Steam after apparently crashing Valve's servers

While some of you might be holding out for Deltarune as one of the Switch 2 launch games tomorrow, the long-awaited indie RPG is actually available today across PlayStation and PC. A decade after Undertale's quaint Steam launch, Deltarune is now topping the platform's global top sellers chart, enjoying orders of magnitude more players, and may have temporarily crashed Valve's checkout servers.

You can head over to Steam's global top sellers page if you want to see Deltarune's current success for yourself. As I write this, it's at the top of the charts, beating out the likes of Counter-Strike 2, Dune: Awakening, and Elden Ring Nightreign.

That's despite the fact that it was apparently impossible to buy Deltarune – or any other game on Steam – for a few minutes after launch. You'll find numerous reports on social media about Valve's checkout process breaking at Deltarune's launch time, and I can confirm that, yeah, trying to buy something was giving a big ol' error message at the time.

DELTARUNE NEVER from r/Deltarune

You'll find many, many, many social media posts from fans jokingly celebrating their apparent role in the Great Steam Checkout Crash of June 4 2025, and I'm not inclined to doubt they had a hand in it.

Deltarune also launched to a peak of 133,930 concurrent players, as SteamDB shows, which is a far cry (and a 12,865% increase) from Undertale's day one player peak of 1,041. The original game's Steam charts tell the tale of a title that spread through word of mouth, and with Deltarune's performance today, it's clear that the word never stopped spreading.

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