For one puzzle, the player has to sneak past a trapped rat without being eaten. The gamemakers put a real dead rat on a scanner to make the image. The gamemakers said the only reason they didn't do this with spiders was because the heat of the scanner would turn the spiders' bodies into gas. They also used many live cockroaches and a real dead catfish. They hired a professional cat trainer to manage the real cat, and this cat was not killed or harmed.