Comparison:Furious Demon God Gai vs. Mig

Was an Ashu
Killed Eiji's father

Took out Dark Shadow

Was almost destroyed by The Duel Crusher but Hyouga jumped in the way

Tried to avenge Hyouga but ended up getting destroyed

Arch Preist Gajah brought revived him and Grand Beast Rei with the Goardom Engine

Became a Quester after Arch Preist Gajah brought him back to life

Betrayed Arch Priest Gajah

Hunted for precious to create Quester Robos

Destroyed by Eiji in the end

Never freed Ouga