the battle royale approach has also been used in games from genres not normally associated with shooter games. "tetris 99" is a 2019 game released by nintendo for the nintendo switch that has 99 players in a game of "tetris" at the same time. players can "attacks" on other players for each line they complete, attempting to become the last player standing. while there have been several battle royale games, the genre has seen a number of games have bursts of popularity before their player count drops. in contrast to other multiplayer-only games, the large number of players typically involved in battle royale games generally require a large enough concurrent player base for matchmaking in a reasonable amount of time. "the culling", by xaviant studios, was released in early access in 2016, and was designed to be a streaming-friendly battle royale mode for 16 players. however, following the release of "battlegrounds", "the culling" lost much of its player base, and a few months after releasing the full version of the game, xaviant announced they were ending further development on it to move onto other projects. "radical heights" by boss key productions was launched in april 2018 but within two weeks had lost 80% of its player base. "sos", a battle royale game released by outpost games in december 2017, had its player counts drop into the double-digits by may 2018, leading outpost to announced the game's closure by november 2018.