O

Ozaru

  
This is the strongest form of a normal Saiyan. When Anyone becomes Ozaru, His powers increases Ten times.

Olibu

 
He is a fighter. He was defeated by Pikkon in a Tournament.

OX King

  
He is the father of Chi Chi. Goku is his son in law.

Oolong

  
Oolong (Uron) is a shapeshifting, anthropomorphic pig that uses his abilities for his own greedy desires. He was expelled from shapeshifting training for stealing the teacher's underwear, so he lacks the ability to change his form for more than five minutes at a time without a break. He joins Goku in the search for the Dragon Balls to eventually steal them, but abandons this plan. In Dragon Ball Z, he is often in the company of Roshi.