Dai Satan is a mysterious evil entity who appears as a giant floating blue-skinned head. He is the ultimate antagonist of Kyoryu Sentai Zyuranger.
At the beginning of the world, Dai Satan battled Ultimate Daizyujin with the demon banished into another world while his divine opponent was splintered into the seven Shogozyu.
When Bandora lost her son 170 million years prior to the series, she traded her soul to Dai Satan for the power to destroy the dinosaurs and lay waste to Earth.
In the series, Bandora usesn Satan's Tower to summon her master to help upgrade her Dora Monster Zombie Franke into Satan Franke. After Satan Franke was killed by Zyutei Daizyujin, the Zyurangers used Ultimate Daizyujin to drive Dai Satan off.
In the finale, Great Satan brought Bandora's son Kai back to life to cement the deal.
After Bandora used her magic to make King Brachion sink into the ground, she used Satan's Tower to summon her master once again and helped to recreate Dora Talos, who Kai used to severe Daizyujin's left arm and half of Dragon Caesar's tail.
Dai Satan was destroyed by Ultimate Daizyujin in the finale just before doing away with Kai and Dora Talos forever.