Deltarune Surpasses Undertale’s Peak Concurrent Players on Steam by 12 Times After Release of Chapters 3 and 4

Deltarune has surpassed the concurrent online player count on Steam of its predecessor Undertale by 12 times on the day it received a new content update, which brought chapters 3 and 4 to the game on June 4, 2025.

As of the time of writing, Deltarune already features an “Overwhelmingly Positive” rating on Steam, with 9,280 reviews, all of which appeared after the game was updated.

As Gaming.News reported earlier, Undertale had recently beaten its concurrent player record on Steam of 10,473, a decade after its original release in 2015, and reached a new peak of 11,071. But according to SteamDB, Deltarune hit a mark of 133,930, exceeding its predecessor’s record by 12 times in just one day after new content dropped.

In Deltarune, players control a human teenager, Kris, who is destined to save the world together with Susie, a monster, and Ralsei, a prince from the Dark World.

Notably, Deltarune, which is available on both macOS and Windows PCs, Nintendo Switch, PlayStation 4|5 and Nintendo Switch 2, will support cross-buy functionality for both PlayStation and Nintendo platforms.

By the end of 2015, according to Steam Spy, Undertale was one of the best-selling games on Steam, with 530,343 copies sold. As of 2025, the game has sold over 5 million copies on Steam alone, while total sales are estimated to be up to 10 million. As of the time of writing, Deltarune’s predecessor featured an “Overwhelmingly Positive” rating on Steam with 243,965 reviews.