The annual Steam Summer Sale is now live and, as usual, there’s a new mini-game for people to play while they empty their wallets.

This year’s sale features some deep discounts on the “Fallout” franchise, 40% off the recently released JRPG “Ni No Kuni II,” the first ever sale for popular battle royale title “PlayerUnknown’s Battlegrounds,” and more. It runs from now until July 5.

The new space-themed minigame is called “Saliens.” Players can customize their saliens, pick a starting planet, and team up with friends to compete for galactic domination. If their group defeats the most enemies on a tile, they’ll claim it as their own. The groups with the most tiles when a planet is taken will get to plant their flag and claim it as their own. Players who take over planets have a chance to win Steam trading cards and free games.

“Committed to fighting The Duldrumz wherever they are found, The Saliens have launched a daring campaign to free the abducted games so that humans and extraterrestrials alike can enjoy the Summer,” Valve said.

The “Saliens” mini-game runs until July 4 at 10 a.m. PST. Once it’s over, Valve said players can keep their Saliens. They’ll “go into cryostasis and get some well deserved rest,” Valve said. They’ll still be visible in Steam profiles, along with any cosmetic items people collect during the sale, “until it’s time for it to wake up again.” Which means the mini-game could make a comeback during future sales. Limited Steam accounts are welcome to play “Saliens,” Valve said, but their battles won’t contribute to the progress on a tile or planet, and they’re ineligible for the giveaways.