The PS2 version became the PS2's first title to sell over a million copies. Eventually, it went on to surpass two million units worldwide.
Most of the demons are named after characters from Shakespeare's play, Hamlet: Guildenstern, Reynaldo, Osric, Marcellus, Hecuba, and Fortinbras.
This game was supposed to be a new Resident Evil game. In the original plotline the virus has spread to Japan and you would have to fight zombies and monsters with a sword, set in the Sengoku period and featuring a "ninja house" filled with booby traps, similar to the mansion from Resident Evil: "The house will contain hidden doors behind walls, ceilings that fall down to you, scrolls and ninja magic, and many other ninja techniques." The project was originally intended for the Nintendo 64's 64DD.
Capcom had a prototype running on the Playstation 1 system. During production they decided to release this on the Playstation 2 as a first year title.