In the Game Boy Color version, entering Left, Up, B, A, Right at the records screen will take the player to a hidden menu where they can use the sound test and a graphics viewer.

In the PC version, there exists three unused boss levels titled "subboss.col, spaceboss.col, halloweenbossb.col" suggesting that such boss levels were at one point planned to exist.

Originally this game was planned to have a Nintendo 64 release, similar to Glover, however this version was cancelled for unknown reasons and all that remains is a largely unfinished prototype version.