The Binding of Isaac: Repentance came out earlier this week, adding loads of new content to the popular roguelike. In addition to bringing new items, characters, and bosses into the mix, the DLC also added an alternate path for players to explore. For longtime fans of The Binding of Isaac, it's almost like learning a brand new game.

Repentance also made a few dramatic changes to many core mechanics. Fans of the roguelike will need to reconsider how they approach their runs if they hope to beat the new bosses and unlock all of the available content.

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Repentance adds two new playable characters to The Binding of Isaac, both of whom first appeared in the Antibirth mod that Repentance is based on. Unlocking them will take some work, but doing so will allow players to earn powerful new items.

The first new character is Bethany, who can be unlocked by beating a run on Hard Mode as Lazarus without using an extra life. She's unable to use soul hearts and black hearts as health, instead storing them as a unique kind of charge that she can use to activate partially charged items. This gives her the potential to spam powerful effects multiple times.

The other new character in The Binding of Isaac: Repentance is actually two characters: Jacob and Esau. The brothers do everything in tandem, but can be made to move independently by holding down the Control key. They have separate health bars and stats, so players will need to think carefully about how they spread out their items. They can be unlocked by beating a new secret boss.

The Binding of Isaac: Repentance also adds new levels to the game, which players can choose to explore if they'd like to fight the new boss. These levels can only be accessed once Hush has been beaten three times. Doing so will unlock an achievement called "A Secret Exit," which gives players the option to explore an alternate level each time they're about to descend to the next floor.

These new levels are some of the most unique areas ever added to the game. Many of the enemies can't be encountered anywhere else, and utilize tactics that will require a lot of trial and error to reliably beat. The new areas also feature puzzles, which are rarely seen elsewhere in the game. Each alternate level also has a unique story event that allows players to retrieve the items needed to fight the secret boss. These events are the closest The Binding of Isaac has ever come to including in-game cutscenes, and they're an excellent change of pace from how the story is normally told.

One of the biggest changes to gameplay in The Binding of Isaac: Repentance is the way that stores work. They no longer require a key to enter on the first floor of a run, but that's the only way they've improved. Stores are now far less likely to contain a restock machine, meaning that players won't be able to re-roll the items on sale. Players can only bomb restock machines once before breaking them, further limiting their use.

These changes make it more difficult for TBOI players to buy their favorite items over the course of a run, and it's not uncommon to leave the shop in Depths II with a glut of extra coins. Though this is an annoying adjustment for players who go into a run hoping to replicate their favorite builds, it actually allows players to spend gold more freely. In many cases, the most valuable item a store can offer is a soul heart, as they make it easier to earn Angel and Devil Rooms.

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Players who take no red heart damage on a floor are still able to earn Angel and Devil rooms, but they act a little differently now. Up until a few days ago, players who earned a Devil Room but didn't take any items had a chance to earn an Angel Room on a subsequent floor. In Repentance, players can now guarantee that they'll earn an Angel Room by not going into the Devil Room at all. This makes it much easier for players to guarantee that they'll collect enough Key Pieces to fight the old endgame boss, Mega Satan.

Devil Rooms are also more expensive than they used to be, with prices adjusting based on Isaac's total number of hearts. It's now much harder for TBOI players to underpay for Devil deals, which used to be part of their appeal. One especially notable change is that the Abaddon item now grants two extra black hearts instead of six, making it far less of a no-brainer to take.

Perhaps the most jarring change in The Binding of Isaac: Repentance is the difficulty spike in Hard Mode. Enemy projectiles move significantly faster, putting the muscle memory of Isaac veterans to the test. Soul hearts are also much more difficult to come by, which in turn makes Angel and Devil Rooms far less common. TBOI has always been a difficult game, but it used to be easier for players to lean on their knowledge of the game to make up for slower reflexes.

The rework to shops has been an especially unpopular change in Hard Mode. In addition to the updates previously mentioned, there's also a chance for shops in Hard Mode to spawn with fewer items than normal, making it far less likely that players will find anything they want.

Though the changes to Hard Mode have generated some criticism about the game's difficulty, Isaac creator Edmund McMillen remains proud of the expansion. In a Twitter thread posted Thursday, McMillen reminded fans that "new enemies, bosses and mechanics will always feel hard till you learn how they work." The Binding of Isaac has always been a game about trial and error, with a heavy emphasis on error. Though there will be some growing pains as players acclimate to Repentance, there's a wealth of new content to explore once they do.

The Binding of Isaac is available on PC, Nintendo Switch, PlayStation 4, and Xbox One.

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