Co-op, Crossplay & Solo Play in The Mound

The two questions that come up over and over about The Mound are "can I drag my console friends along?" and "is this any fun on my own?" Good news on the first, a more nuanced answer on the second. Here's the full picture of how multiplayer works in ACE Team's co-op horror, drawn from the developers' own comments and the Steam store details.

Is The Mound co-op or single-player?

At its core, The Mound is a co-operative game for one to four players. The entire loop is built around a squad: you gear up together aboard the galleon, take a contract from El Capitán, and descend into the jungle and the ruins of K'n-yan as a team. Splitting duties — who carries the light, who hauls the loot, who watches the rear — is the whole point.

That said, the developers have confirmed they're supporting solo play and an offline mode. So you can go in alone. The catch is that nothing about the design is built to make a lone explorer's life easier — the difficulty, the enemy behavior, and especially the sanity system all assume you've got backup. More on why that matters below.

How many players can join?

Up to four players in a single expedition. That's the sweet spot the game is balanced around: enough hands to divide jobs, few enough that one person's mistake — or one person's sanity break — can sink the whole run. There's no larger raid mode or PvP; this is strictly a small, co-operative crew against the dark.

Does The Mound have crossplay?

Yes — and this is one of the game's better features. Crossplay is supported across all three platforms, so a squad can mix and match freely:

• PlayStation 5
• Xbox Series X|S
• PC — on both Steam and the Xbox PC app

In practice, that means your friend on PS5 can drop into the same expedition as you on Steam, with a third crewmate on Xbox. For a game whose whole hook is co-ordinating with the people you actually know, not being walled off by platform is a big deal — it's the difference between a squad that fills up and one that never quite comes together.

How does matchmaking work?

There are two ways to get into a game:

• From the galleon hub — the ship doubles as your social space. From a lobby menu there, you can host your own session or jump into someone else's.
• From the main menu — a more traditional multiplayer menu that opens a lobby directly, for when you just want to queue up and go.

Both routes get you to the same place: a crew of up to four prepping for a contract. If you're rolling with friends, the hub is the natural meeting point; if you're going in with randoms, the main-menu lobby is the quick option.

Should you actually play solo?

You can, but go in with the right expectations. The reason a lone run is brutal comes down to the sanity system. As your mind frays, the world starts to deceive you — and it does so per player. Paths disappear, and teammates can start to look like the monsters you're hunting. With a squad, voice chat becomes your reality check: someone can confirm that the door really is there, that the "creature" stalking you is just your panicking friend.

Alone, you lose that anchor entirely. There's no one to call your hallucinations, no one to revive you, no one to split the load so you're not over-encumbered and slow. If you want to see how punishing that gets, our survival guide breaks down the co-op roles that keep a crew alive, and the bestiary covers the creatures you'll be facing with — or without — backup.

Bottom line: round up to four, mix platforms freely thanks to crossplay, and keep voice chat open — it's not just for banter, it's your defense against the sanity system. New to the game? Start with our release date, platforms & price breakdown, then prep your loadout in the expedition planner.