Warframe is a PC/Mac/Steam game that takes place in a post-apocalyptic world

The game starts out in a post-apocalyptic world where a mysterious being known as Orokin called The Watchers have recently attacked humanity. They are a force that only a few people know of, but are known to be in control of everything. Their goal is to destroy humanity, but a handful of survivors have banded together to create something they think might help humanity get back to where they were, The Prime. Now you play as a human, known as a Tenno who is the protagonist of the story. You can choose which side you want to take part in and the game will progress based on how you choose.