The developer of “PlayerUnknown’s Battlegrounds” (PUBG) is suing Cary-based Epic Games, the creator of “Fortnite.” Here’s a look at what’s happening.

The Korea Times reported this week that “PUBG” (pronounced pub-gee) is suing Epic Games for copyright infringement, saying that the “Fortnite” creator purposefully copied “PUBG” in its creation of “Fortnite.”

One PUBG official said the firm filed an injunction against “Fortnite.”

“We filed the suit to protect our copyright in January,” said the official.

Fortnite” and “PUBG” are both first-person shooter games that pit players against each other in a battle royale, last-man-standing style of game.

Fortnite” originally only had a “Save the World” mode, which was akin to a game’s normal campaign mode.

But in September, the game added a battle-royale mode, where players could battle each other in the last-man-standing format.

PUBG, a subsidiary of Bluehole, said it was unsure how to respond to the game’s new mode since its “core elements” and user experience appear to be the same.

The two firms have been connected before. Back in September, Bluehole vice president Chang Han Kim said in a press release that the company wasn’t thrilled with its new competitor, especially since “PUBG” uses Unreal Engine 4, which is developed by Epic Games.

“After listening to the growing feedback from our community and reviewing the gameplay for ourselves, we are concerned that Fortnite may be replicating the experience for which PUBG is known,” Kim said in a release, according to Mashable. “We have also noticed that Epic Games references PUBG in the promotion of Fortnite to their community and in communications with the press. This was never discussed with us and we don’t feel that it’s right.”

Both games have become immensely popular over the last year. PUBG has sold 40 million copies so far, including one version for the Xbox One, according to The Verge.

Meanwhile, “Fortnite” has made nearly $300 million in April alone, even though it’s a free-to-play game.

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