Explore a house and discover it's story. You're alone, there's nothing to really "do " just explore, discover the story and enjoy

Not too hard, beautiful 3D platformer with a touching story

Not only more Portal but also with more players. Coop play is 50% of this game and it's best feature. Find a friend and solve puzzles together.

Included as a freebie in the Orange Box by valve and turned out to be the start of a 3D platformer revolution. One of the best games ever.

A portal "mod" that is nearly at the quality of the original. Get a gun that can shoot paint instead of portals and GO !

Assasin's creed but with a combat part that's really nice. Also procedurally generated enemies & behaviors. Fight and enjoy it.

A Telltalle game (Lot of story & choice, nearly no other interactions). The best one for now.

A story-driven game by the team that did Heavy Rain & Beyond: Two Souls. It's the only one on PC and was the first but still very enjoyable.

Create destruction & killing machines. Still in early access and very short, the game look really nice and show great promises.

Like a lego ship-builder where you can fight other player inventions (Piloted by the game) with your own and conquer the galaxy