Unused Content

Phantom Beginning Classic
In the source code of the game, there are two versions of the Metropolis Zone map; the completed version and a broken version where no backdrops have any collision detection, and thus cause Knuckles to fall off-screen and die. Other notable differences in the broken map are that the top section would have one of Star Light's fans try to stop you from reaching the lone 1-up in the stage. This was changed to springs bouncing Knuckles back, and the 1-up concealed in a hidden room.

Friendship: A Sonic 2 Creepypasta
There are several frames in the game that go unused, such as a normal Sonic 2 options menu, the Green Hill Zone Act 1 level, as well as a crash screen and an anti-piracy screen.

The Anti-Piracy screen was planned to be used with some coding to determine whether the game was actually purchased for money, but because this couldn't be coded in, the game went without it.