Mann vs. Machine, a new cooperative game mode for Team Fortress 2, is set to arrive on August 15.

The free update for Valve's free-to-play shooter, lets you and five friends fight off a lethal horde of robots on all-new maps. Players will need to work together in order to survive and upgrade weapons and abilities.

Successful combatants will earn incredible loot and unlock brand new achievements.

Valve also announced a major update to the Steam Community, focusing on highlighting the best user-created screenshots, videos, and Workshop items. Every game will have its own new Game Hub to house all the content and give players a central location to talk with other players.

"The New Steam Community is all about showing off the best content that gamers have created," says Emily Kent at Valve. "With over 89 million screenshots, videos, Steam Workshop maps, levels, mods, and items, plus news articles and product updates, the community has created an unbelievable wealth of content around their favourite games."

Valve has promised feature previews daily until August 16.