In this unknown age Earth is in ruins and under Towa and Mira's tyrannical rule. This age serves as a base of operation for Towa and Mira and to recruit villains from different timelines such as Turles and Lord Slug. Towa and Mira create a wormhole to capture Bardock and to bring him into the unknown age.
Towa recruits Broly and Janemba and brings them to the unknown age. Time Breaker Bardock brings energy to Mira.
The second Future Warrior and Future Trunks manage to get to the unknown age from the wormhole created to capture Bardock and they confront the Time Breakers. Bardock manages to break free from Towa's mind control and sends Mira to the Time Rift. The second Future Warrior and Future Trunks encounter the 1st Future Warrior whose being controlled by Towa and manage to break him free. However Towa travels back in time to erase the 1st Future Warrior from history.
The second Future Warrior follows Towa and Mira to the unknown age to retrieve Tokitoki's egg. After fighting Mira he absorbs Towa and Tokitoki's egg, where he obtains a new form. Goku appears with the help of Whis and helps the second Future Warrior fight Mira by transforming into Super Saiyan Blue. The second Future Warrior and Goku manage to defeat Mira and they retrieve Tokitoki's egg.
In Xenoverse 2, the battle stage for Age ??? is named Earth from an Unknown Time (which is basically an alternate story mode exclusive version of the West City Ruins stage with a dark purple sky).