More than a few games have followed in the footsteps of The Room, exploring tactile hands-on puzzle solving through different themes. Games like House of Da Vinci have gone for a familiar Victorian style, but Returner 77 designed its rooms and puzzles with science fiction flair. Now the game’s final chapter, titled The Den, is available on iOS, added in a recent update.

Returner 77 tasks you with exploring an attacking alien force’s crystal ship, in the hopes of finding a way to save Earth. Within its odd corridors and otherworldly rooms rest machinery and extraterrestrial contrapations to interact with, letting you progress deeper into the vessel and through the game’s five chapters. Rotating objects, interacting with weird devices, activating switches and portals are your means to completing Returner 77’s challenges. 

The final chapter, The Den, adds an anti-gravity twist to the gameplay, granting you greater movement to jump around the chapter‘s enviroments to solve its puzzles and find secrets in your quest to the conclusion.

Returner 77’s sci-fi puzzles and story of apocalyptic threat can be purchased on iPad and iPhone for $4.99.