http://www.pcgamer.com/the-binding-of-isaac-cave-story-lead-steam-weekend-sale/

Indie publisher Nicalis, Inc. is hosting a sale on Steam this weekend, leaving a handful of great indies heavily discounted through tomorrow, Saturday, December 4. The headliner is beloved roguelike The Binding of Isaac, as well as a bunch of confusing DLC. 

While the original game is $1 at 80 percent off, the definitive version of the game, The Binding of Isaac: Rebirth, is $10 at 33 percent off. Rebirth greatly improves the art, controls and music, and adds tons of items, enemies and bosses.