The Binding of Isaac: Afterbirth + is essentially the complete version of the excellent faeces-filled twin-stick roguelike by Nicalis and Edmund McMillen, and it just got updated with a surprisingly large free update. The Forgotten Update brings with it a bunch of changes, most notably a number of new in-game items and unlocks, as well as more than 800 new rooms for players to overcome/explore. You can read the full patch notes if you want to get a clearer idea as to the extent of the changes made in what sounds like it could be the last major update for the game.