Core Keeper’s first Steam Free Weekend since the 1.0 launch runs from October 8 through October 12, 2026. It includes the full game and online multiplayer, so new players can bring friends into the real co-op loop instead of testing a tiny demo slice.

That makes this a clean entry point for anyone who has been curious but never wanted to buy blind. The sale helps too, but the free weekend is the useful news: you can test the mining, base building, bosses, farming, fishing and multiplayer before spending anything.

Core Keeper players build and explore an underground base.
Image: Pugstorm.

The Full Game Is Open

Pugstorm says the free weekend gives players access to the full Core Keeper experience rather than a limited demo. Online multiplayer is included, which means a group can see whether the underground routine actually works for them before the event ends.

The event also leaves the game and save data in your Steam library after the weekend. If you buy Core Keeper during or after the event, you can continue the same save instead of starting over because the trial expired.

The Dates And Sale Details

The event runs from Thursday, October 8 through Monday, October 12. Check the live Steam event page for the exact regional end time before planning a final co-op session; the announcement gives the date range, but not one universal clock time for every region.

A 40% discount runs alongside the free weekend. That gives a group time to try the same world, see who actually enjoys the digging and crafting loop, then decide whether the discounted purchase is worth keeping the save alive.

Core Keeper characters face enemies in an underground arena.
Image: Pugstorm.

What New Players Should Test First

Do not spend the whole weekend building a museum and forget the game’s pressure. Push far enough to test exploration, one boss fight, a basic base, and the multiplayer rhythm of splitting jobs without losing track of each other.

The useful question is simple: does your group enjoy the loop after the first shiny discovery wears off? If one player likes farming, another likes wiring the base, and someone else wants to pull bosses into a bad situation, the full weekend gives you enough room to find out.

The Practical Verdict

Download Core Keeper before the free weekend closes if you have been waiting for a low-risk co-op test. The full game, online multiplayer and retained saves remove the usual trial limitations. If the group clicks with the underground routine, the 40% sale is there; if it does not, you lose a weekend, not a full-price purchase.