The Binding  of Isaac: Repentance is a DLC for The Binding of Isaac: Rebirth, which is a remake of a classic RPG rouge-like shooter. The game centers around Isaac, whose mother starts hearing the voice of God demanding a sacrifice to prove her faith. Isaac tries to escape his mother by going into the basement where he faces enemies he has to fight through and finds treasures along the way as he tries to get to safety. 

Repentance is going to be released on March 31, 2021 for PC but there is still no date for console players. Edmund McMillen says the DLC will, "expand the game greatly, adding tons of new bosses, floors, alt paths, items, story elements, challenges and a few amazing characters (and more!)" and it has been called a "sequel-sized final expansion". Repentance was announced by McMillen on the games' nine year anniversary and can be added to you Steam wishlist for when it comes out.

The new content that will come from the DLC includes over 130 new items, 100 enemies, 25, bosses, 2 playable characters, 5,000 potential room layouts, 100 achievements, new chapters, and a new final boss and ending. The Steam page reads, "It's a game too big to be called a sequel: Repentance takes Isaac to new heights of roguelike dungeon adventure, as the brave boy descends into the basement for his greatest challenge yet, Isaac's new quest takes him to unknown places he's never been, filled with horrible new enemies and bosses, weapon combos you've never synergized before and items he's never seen... unholy terrors from his wildest dreams and worst nightmares!" The link to the new trailer can be found here:

The Binding of Isaac: Repentance Release date trailer

source: gamesradar.com