Superman may be faster than a speeding bullet and more powerful than a locomotive, but his arrival in the fast-growing gaming genre may have been too little and too late.

Last month, Warner Bros. Interactive Entertainment announced it would pull the plug on "Infinite Crisis," its superhero-themed entry into the lucrative multiplayer online battle arena genre—better known as MOBA—only two months after it launched.



It was the highest-profile retreat in the white hot strategy-and-fighting category yet. The U.S. user base for MOBAs has surged to about 28 million monthly active users from 2.2 million four years ago. Some market watchers are taking the fall of "Infinite Crisis" as a sign U.S. user growth has peaked for now and new entrants will have a tough time breaking into the space.

"Most MOBAs are exceedingly complex games," SuperData Research CEO Joost van Dreunen said in a research note. "Players who have invested substantial time to master one game are unlikely to jump ship."



MOBA is a strategy subgenre in which two teams launch coordinated attacks on one another's base. It rose to prominence with the launch of Riot Games' "League of Legends" in 2009, and has fueled the growth of competitive gaming and live video game streaming. MOBAs are generally free to play, but developers make money from in-game purchases.

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The genre peaked at 29 million monthly active users in the U.S. last August, according to SuperData Research. In May, that metric stood at 28 million, van Dreunen wrote.

The MOBA space has grown and dipped at pace for the last five years with little volatility. But following the holiday season last year, when gamers shifted their attention to big releases, SuperData noticed the U.S. market plateaued after bouncing back in January. That could be a sign the genre has matured, said van Dreunen.