The Callisto Protocol

In The Callisto Protocol, players assume the role of Jacob Lee from a third-person perspective. E. Device". Health can be replenished with injectable packs found throughout levels.

Jacob can use weapons to combat enemies, as well as a melee system to dodge enemy attacks while looking for openings to strike and kill them. Both combat styles can be mixed up, providing greater variety when facing enemy types. Jacob can collect and review audio logs during gameplay.

In 2320, Jacob Lee (Josh Duhamel) and Max Barrow (Jeff Schine) are contract freight transporters working for the United Jupiter Company (UJC). The two decide to retire after ferrying one last shipment between Europa and the UJC-operated Black Iron Prison on Callisto. Shortly after leaving Black Iron in their ship, the Charon, they are boarded by the Outer Way, a terrorist group purportedly responsible for a massive biological attack on Europa, and the ship crash-lands back on Callisto. Max is killed, leaving Jacob and Outer Way leader Dani Nakamura (Karen Fukuhara) as the only survivors.

They are recovered by Black Iron Prison security head Captain Leon Ferris (Sam Witwer) and incarcerated on the orders of Warden Duncan Cole (James C. Mathis III). After an intake process, Jacob awakens to find the prison overrun by hostile "biophages", inmates afflicted with an unknown disease. He encounters Elias Porter (Zeke Alton), a prisoner who claims to have an escape plan.

The origins of The Callisto Protocol began with the formation of Striking Distance as a studio within PUBG Corporation (now PUBG Studios) in June 2019, helmed by Glen Schofield, who had previously co-created the Dead Space series at Visceral Games. The studio was created to expand the PUBG: Battlegrounds universe by creating a narrative driven game. Schofield said that when he met with PUBG Corporation where they explained their goal to expand the PUBG narrative, he already had the concept for The Callisto Protocol in mind and presented that to them and worked with them to fit his idea into their universe. However, by May 2022, Schofield stated that the game had grown to be its own story and is no longer connected to PUBG, though there remain small nods to the latter.

Schofield wanted to keep the game grounded in reality to some degree, and thus selected a potentially human-colonizable location like Callisto as the setting. The moon has been theorized to have a subsurface ocean of water, which Schofield believed could offer a mystery to tie into the game.

The Callisto Protocol received "mixed or average" reviews from critics, according to review aggregator website Metacritic.

Several publications noted that The Callisto Protocol suffered from stuttering and performance issues, primarily affecting the PC version; as a result, the game received "mostly negative" user reviews on Steam upon release. The same day, the game received an update that alleviated shader compilation stutter, with further optimization patches being promised by the developers. Glen Schofield later said that the technical issues were the result of a "clerical error" from the game's development team.