The Dai Mazines are a group of giant mecha that serve the Demon King Oma Zi-O in the future and antagonists in Kamen Rider Zi-O.
Created at an unknown period in time, the Dai Mazines were used by Oma Zi-O in his conquest of the world to exterminate half of all life.
After Sougo destroyed his Ziku Driver, erasing Oma Zi-O in the future, the Dai Mazines became dormant and sank into the ground.
The Dai Mazines were later seen when Swartz abducted a group of children on a bus and transported them to the future where a city was being destroyed by the Dai Mazines. Swartz tells the children that only a king could survive a cataclysmic event such as this. Just then, Sougo uses his time powers on a Dai Mazine to age it into dust.