Strangely, only the NES port has an Easter Egg referencing ICOM Simulations' other popular adventure "Déjà Vu": In an out of the way corner of a late game labyrinth section, the player can find a tombstone of one "Ace Harding", the main protagonist of "Déjà Vu". Messing with the tombstone will cause a zombified Ace to appear, proclaiming he was once a famous detective, and all he wants now is to be left alone. Further irritating him results in one of the many instant in-game deaths.
Contributed by DarkChojin