ROZ begins in Ethereum Blockchain, following an outbreak of the so-called Zther Flu, a highly contagious virus whose symptoms include significantly increased aggression and the loss of many higher brain functions within those infected.

At the beginning of the epidemic, three individuals; Bill, Joss and Louis are in Miami, where Bill first got infected by the new Zther virus ERC-721 strain. The virus is evolving turning him into zombie and the mutation made each zombie unique (1/1). Soon Joss and Louis got infected as well and the trio start to infect more humans and fought their way through blockchain to get 9.997 others infected. There are no cure.

All the zombies gathered at the train station, finding several damaged trains and a locked chest. They figured they need to repair the train, open the chest and use it to make their way to the city of Zxreum, where they decide the future of ROZ.