The makers of Fortnite, one of the world’s most popular video games, have been accused of copying rival title PlayerUnknown’s Battlegrounds (PUBG).
The studio behind PUBG has asked a court in South Korea to determine whether Epic Games copied its intellectual property.
Fortnite and PUBG have both attracted millions of gamers with their huge “last player standing” online battles.
Epic Games has not yet commented on the lawsuit.
PUBG was first released in March 2017. It was inspired by the Japanese thriller film Battle Royale, in which a group of students is forced to fight to the death by the government.
In PUBG, up to 100 players parachute on to an island, search for weapons and kill one another until only one player remains.
Fortnite was first released in July 2017 but its Battle Royale mode was not added until September 2017.