GTFO is a gritty, hardcore co-op FPS set in the godforsaken bowels of a high-tech prison. That’s a pretty solid concept for a shooter on its own, but 10 Chambers Collective is adding a new dynamic to the formula. Rather than a static set of missions, GTFO will have a constantly-evolving expedition structure called the Rundown.

Here’s how that’s going to work: At any given time in GTFO, there will be a specific Rundown active for all players. 10 Chambers says this is a ‘work order’ from the prison warden, and it specifies a certain set of expeditions for players to embark upon. The upper levels are the simplest and easiest, but as you take on expeditions deeper into the facility’s depths, things get more challenging and the rewards get more enticing.

Each Rundown has a timer running, and you’ll have specific challenges to take on during each one. Once the timer is up, the set of missions and challenges available will be replaced. 10 Chambers says the number and type of challenges will vary, and some Rundowns will last for a couple weeks, while others may run for multiple months.