You could put together a decent indie games showcase for nothing just by loading the Epic Games Store and clicking a button. The current freebie on there is Polytron's excellent, world bending puzzle-platformer, Fez. It's definitely worth the zero doubloons they’re asking for it. In fact, it’s worth at least 100,000,000 times that. Fez is great.
It seems a given that there’s more to the game than meets the eye. It’s a 2D plane wrapped around a 3D game world. You can only move side to side, or jump and fall, but the world moves around. An impossible jump becomes possible with a shift of focus, shifting the view 90 degrees and moving a background block into the perfect platforming position. Over seven years after release, it still feels novel and fresh.
But that’s just the tip of the dimension. Fez has so many secrets to unveil that a whole slew of websites and communities were devoted to decoding the strange glyphs that hid the game’s real story in plain sight. I’m only on the news beat this week, so I don’t have the time to write them all up, but the late Killscreen site has a good read on the lengths the community went to to unlock Fez's extra dimensions. You absolutely can play it as an over-talkative platformer, but there's more there for those who take the time to look for it.