Dota Underlords has become the next multiplayer craze on Steam, regularly maintaining a concurrent player count that has competed with veteran titles like CS:GO and Dota 2 itself. Dota Underlords is Valve's version of the popular Auto Chess mod that has essentially spawned its own genre in the form of autobattlers.
Interestingly enough, Dota Underlords is basically following the same blueprint Dota 2 did in becoming a worldwide phenomenon. Dota 2 is the sequel to a mod that was made for Warcraft 3, while Dota Underlords is a spin on the Auto Chess game that was made as a mod to Dota 2. It's the circle of life for Valve, as the company has frequently made good on community-based mods or ideas, converting them into official games that suddenly become global phenomena with the power and reach of the Steam digital distribution service. That's especially important with the Epic Games Store threatening Valve's long-standing monopoly on the practice—the more platform-exclusive games that Valve can tempt fans with, the better Steam's standing remains in the eyes of a PC userbase that is beginning to explore its options.
As of this writing, Dota Underlords maintains its position as one of the most-played games on Steam just over a day after its official launch. While Dota 2 and CS:GO have regained their lofty positions as the two most popular games on Steam, Dota Underlords has been fluctuating in and out of the top-three positions, currently sitting at fourth. That still puts the fledgling game—competing, of course, with Auto Chess itself as well—ahead of Rainbow Six Siege, Grand Theft Auto 5, and Warframe.
Contextually, it's also a major win for Valve itself. While Dota 2's all-time high concurrent player count is ridiculously high, the rest of its games haven't fared so well, with Team Fortress 2 peaking at just under 123,000 while Artifact only managed a peak of around 60,000 during its extremely brief time in the spotlight. Dota Underlords has already surpassed both of those titles, with an all-time high currently sitting around 175,000 players. That's an absurd gain in audience in a short period of time, and once again proves that Valve, if nothing else, has its finger on the pulse for which multiplayer mods are worth the developer's official stamp of approval and repackaging.
It's also important to understand that Dota Underlords also launched on mobile, meaning fans aren't even getting a full look at what its player count really looks like. It's a strong start that will likely climb over the course of the next week or two as word of mouth sends more players over to try the next multiplayer craze. It's also going to be a hotly-contested genre soon, with Riot ready to produce its own autobattler in Teamfight Tactics. Just like League of Legends versus Dota 2 before it, the new war between familiar foes in Teamfight Tactics and Dota Underlords will probably be competing for millions of gamers' time and money in the near future.