The game originally had much more graphic blood spurts and the blood was more brightly colored, but was toned down. This however can be activated with a Gameshark.
The Combat Knife was removed in the Japanese version.
Nintendo never officially released the game in Germany (for fear of youth protection laws) but due to its immense popularity everywhere else, the game was imported by wholesalers.
An earlier version featured different weapon models for the game. During production, the models were changed for unknown reasons.