Frieza

Frieza was the greatest fighter in the universe for a time.Even powerhouses like Vegeta and Nappa were as nothing to him. Unfortunately, Frieza let his power go to his head. Piccolo and Nail (who Frieza had unwisely left alive) took him on; Gohan fought him a number of times; and, when Goku fought him , Frieza not only got hit by his full Spirit Bomb, but made the mistake of taunting Goku by hurting Piccolo and killing Krillin. Goku became a Super Saiyan and trounced Frieza thoroughly. Goku made the mistake of letting Frieza stew in his anger, however. Although Frieza was almost crippled and cut in half in space, he lived, and his father, King Cold, discovered him. King Cold bionically recreated him and improved his power. Frieza was then defeated again by Trunks. Frieza then showed up during the Super-Android 17 saga improved, but Gohan's quarter-Saiyan daughter, Pan, was still able to defeat him.

Starting Level

Depends on when you get him.

Abilities

Transform: Frieza transforms into five shapes. His first form has him in a pod. He then appears as a massive horned creature. He then appears as an odd alien creature. He finally transforms into a thin, shapeless creature. His cybernetics are designed for his final transformation.

Equipment:

Cybernetics: Frieza has cybernetics that greatly enhance his power level, although they don't appear to offer him any new moves. Then again, we don't get to see much of him with cybernetics (3 or 4 episodes...)