Featured Article
This article has been recognized for its exceptional quality and comprehensive coverage.
Unknown Worlds Entertainment
Unknown Worlds Entertainment is a game development studio founded in May 2001 by Charlie Cleveland (online handle "Flayra"). The studio is based in San Francisco, California, and operates as a fully remote, globally distributed team of approximately 171 employees. It is a wholly owned subsidiary of KRAFTON, Inc. since December 2021.
History
Natural Selection era (2001-2012)
Cleveland founded the studio to develop Natural Selection, a Half-Life mod combining FPS gameplay with top-down RTS. It released October 31, 2002 as a free mod, co-created with Cory Strader (now Visual Development Lead on Subnautica 2, still at the studio after 17+ years).

Max McGuire joined as co-founder in October 2006 after working as Lead Engine Programmer at Iron Lore Entertainment (Titan Quest). McGuire built a custom engine called Spark for Natural Selection 2. The game released in 2012, reached #1 on Steam, and sold approximately 300,000 copies.
Subnautica era (2013-2021)
Subnautica was announced December 17, 2013 and entered Steam Early Access on December 16, 2014. After roughly three years in Early Access, the 1.0 release landed on January 23, 2018. It became a massive commercial success, selling over 5.3 million copies with over $108 million in Steam revenue.
The standalone expansion Below Zero entered Early Access January 30, 2019 and fully released May 14, 2021. Originally planned as DLC, it was expanded into its own title. Both games were built in Unity.
KRAFTON acquisition and Subnautica 2 (2021-present)
KRAFTON acquired Unknown Worlds in late 2021 for $500 million upfront plus up to $250 million in earnout. See KRAFTON acquisition and controversy for the full account.

Under KRAFTON, the studio began developing Subnautica 2 in Unreal Engine 5. The game was revealed at the Xbox Partner Preview on October 17, 2024. In July 2025, KRAFTON replaced the founders with Steve Papoutsis as CEO.
Studio culture
Unknown Worlds has operated as a remote-first studio for most of its history, predating the industry-wide shift to remote work during COVID-19. The team is distributed globally across multiple time zones.
Games
Item | Description |
|---|---|
Natural Selection (2002) | Free Half-Life mod |
Natural Selection 2 (2012) | Standalone, custom Spark engine |
Subnautica (2018) | Unity, 5.3M+ copies sold |
Below Zero (2021) | Unity |
Subnautica 2 (2026 Early Access) | Unreal Engine 5 |