Ubisoft has revealed a new Assassin’s Creed game, Rebellion, for mobile. The free-to-play, strategy role-playing game is coming “soon” to iOS and Android devices. Assassin’s Creed is a series of stealth-based action games for consoles and PC, and the franchise has sold over 100 million games.

But a successful mobile release could bring in a lot of money. We’ve already seen Fallout, another triple-A game series known for console and PC releases, strike it rich on mobile with Fallout Shelter (which has over 100 million players).

That comparison is even more fitting than you think, because Assassin’s Creed: Rebellion looks a lot like like Fallout Shelter. Players design their own hideouts in a grid-like manner that resemble the vaults you make in Shelter. Rebellion takes place during the Spanish Inquisition, which was also the setting for last year’s Assassin’s Creed movie.

But Rebellion has a cast of characters from across the franchise’s complicated timeline, including the Italian Renaissance’s Ezio. Ubisoft promises that the game will have a roster of over 40 assassins.

This is a big year for Assassin’s Creed. After taking 2016 off after a long stretch of yearly releases (and declining sales), the series is returning this October with Assassin’s Creed: Origins. It takes place earlier than any other title in the series, toward the end of the age of pharaohs in Egypt.

But this mobile game could end up being the bigger money-maker if it’s a hit. We’ve seen other Assassin’s Creed apps on mobile, but they’ve been premium games like the action-based Assassin’s Creed: Identity or older releases like 2013’s Assassin’s Creed: Pirates. A new, successful mobile game can give Ubisoft a boost, especially as it battles a hostile takeover from Vivendi.