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 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. The rework to shops has been an especially unpopular change in Hard Mode.
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. Soul hearts are also much more difficult to come by, which in turn makes Angel and Devil Rooms far less common. Enemy projectiles move significantly faster, putting the muscle memory of Isaac veterans to the test. Perhaps the most jarring change in The Binding of Isaac: Repentance is the difficulty spike in Hard Mode.
