- "There are moments when a single snail can make a world go extinct."
- — Zero, introducing himself to the Decision Game players
The Snail was an animal mentioned in Zero Escape: Zero Time Dilemma. The snail was indirectly responsible for the events that catalyzed the entirety of the Zero Escape series, as well as the apocalypse of 2029 on Earth.
Sometime in 2011, a young mother (implied to be the mother of Eric) was jogging in the park and reached a fork in the road. Normally, she went down one path, but she went down the other since this snail had been on her normal route. Why she specifically avoided walking down the snail's path is unknown. Was she afraid of them? Or felt a sense of danger from it? Whatever the case may be, the snail caused her to switch paths. The woman reported to a senior citizen who was familiar to her that she chose a different path to avoid the snail. This led her to the site of her murder by a girl, who is implied to be Mira.
One day, about a month later, a man was (falsely) accused of, being the killer. He claimed innocence, but the jury still found him guilty. The verdict could not be overturned and he was executed. As a result of this, the man's wife took her own life in despair. The couple left behind two young children, Aoi and Akane Kurashiki.
The accused man called a taxi soon before his arrest; but as a result of his arrest, the taxi did not pick him up but instead picked up another fare, a surgeon who had been scheduled to operate on a young boy named Sean (who a robot would eventually be named after). The taxi was involved in a lethal accident that killed the driver, the surgeon, and by extension the boy the surgeon was supposed to operate on. This accident would not have happened had the driver picked up the accused man.
Because 999 would never have happened if the Kurashiki parents survived, and subsequently neither Virtue's Last Reward or Zero Time Dilemma could have either, this snail indirectly caused the deaths of 6,000,000,000 humans and massive amounts of chaos and suffering.
- The notion that the placement of the snail was unplanned and natural is disputed by some theories:
- There is a theory that the snail was intentionally placed on the road by a radical terrorist of an organization which plans to kill 8,000,000,000 humans. It is possible this terrorist was another esper who had the ability to SHIFT and/or Mind Hack with complex motives, who could foresee the future(s) this snail would bring.
- There is also a theory that Delta placed the snail on the road, since he seems to know about the snail. But this would go against some of his statements, implying a deeper story.
- The archives suggests the snail may have had a leucochloridium inside. A leucochloridium is a parasite that uses snails as initial hosts, and then transfers to birds. The egg originates in the digestive tract of a snail, and then migrates to the tentacles. The leucochloridium causes the tentacle to take on the appearance of a worm or caterpillar, which draws the attention of birds. Once eaten by a bird, the parasite will lay an egg that leaves the body with the feces, which then becomes food for snails, and the cycle continues.