ZERO Sievert 2 is the sequel to cult hit ZERO Sievert, the game that defined the top-down extraction shooter. Set in the devastated country of Zakov, you explore procedurally generated maps, scavenge, face anomalies, bandits, and mutants, and make it out alive.
Building on the high-stakes yet approachable core of the original; It expands the scale, story, systems, and presentation of the original, while introducing co-operative multiplayer, the most requested feature from the original’s dedicated community.
With over 600,000+ copies sold and a successful Kickstarter campaign, ZERO Sievert was a breakout solo indie dev success. It helped establish the top-down extraction shooter genre which includes recent hits like Escape from Duckov (3M+ copies sold). Set 20 years after the events of the original, Zakov expands, opening up the world for both long time fans and new players to explore. Together you will be able to see what changed since the last game, and hunt alongside one another in the genre ZERO Sievert helped create.
Development of the sequel is led by Underdog, a new UK-based indie studio formed by former Splash Damage developers, working in collaboration with the original creator and publisher.
Underdog is an independent game development studio based in London, founded in 2025 by Giuseppe Navarria and Antoine Fion after their time at Splash Damage.
During 2025, they were joined by several former colleagues, bringing together a close-knit team of experienced developers with a shared history and common creative goals.
The studio specialises in co-operative and collaborative multiplayer games, creating experiences built around teamwork, tension, improvisation, and memorable shared stories between players.
Drawing on years of AAA development experience, Underdog is focused on making immersive, collaborative games where every session feels unpredictable, every player has a role to play, and the best moments are the ones people talk about long after they stop playing.