Radical-6

Radical-6 is a lethal airborne and waterborne suicide virus created by Free the Soul that is introduced in Zero Escape: Virtue's Last Reward and an important subject of the story and the series.

First appearing in December 2028, it caused a worldwide pandemic and apocalypse on Earth in the early months of 2029, almost eradicating humanity, as it led to events that caused the deaths of 6 billion people.