Development for "Resident Evil Zero" began for the Nintendo 64 in 1998. The partner system was created to take advantage of the short load times possible with the capabilities of the Nintendo 64 Game Pak. The cartridge format also provided limitations, as the storage capacity was significantly less than that of a CD-ROM. The team had to approach the design differently from previous series entries to conserve storage space. "Resident Evil Zero" was designed to be more difficult than previous "Resident Evil" games. Inspired by "Sweet Home" (1989), the team removed the item storage boxes present in earlier games and introduced a new item-dropping feature. Development slowed when the team encountered memory storage problems, and so production was moved to the newly announced GameCube. The game had to be rebuilt, with only the concept and story carried over.