Zero (LOTSG)

"Are these your friends? I must say you heroes are too easy to outsmart. I just give you a few strong opponents to tire you out and then take out the trash. Don't feel left out though, I'll give your head to my wife as a gift."

- Zero taunting Kaestos about his dead friends Zero is the leader of the Galactic Trade Organization, and is the one who killed the Z-Warriors of Age 820.

Zero's success in doing so resulted in him becoming one of, if not the most, infamous people in Hell.

He is Kaestos' most hated foe, and the only person the Saiyan was ever prepared to wipe out of existence by destroying the tyrant's soul while he was dead.

Background
Zero was born into the Galactic Trade Organization at Age 778, and became its ruler in 789 at only 11 years old.

Zero ruled the Organization with an iron fist, ruthlessly killing anyone in the way of his goals or the stability of his reign no matter their species, race, gender, or age.

His forces were beaten back only once in Age 800, when he was 22 years old by the Z-Warriors.

Zero had sent a battalion to Earth, and later his strongest subordinates; who driven back by a Super Saiyan from Earth.

Zero gaining great interest in the planet,and prepared for an invasion of the only world that had defied his rule.

Present Day
Finally, after twenty years of of preperation, Zero and his army was ready to assault Earth.

Zero had kept an eye on the only planet that defied his rule, making sure to keep up to date on their power, and adjust his armies training regimen accordingly.

His army invaded Earth with his weakest warriors attacking first, and then ascending in strength. Eventually it was down to his Elite Warriors, who were fighting the Z-Warriors in three on one fights.

Zero dispatched three of his elite warriors to Kaestos' location before waiting for his chance to strike the other Z-Warriors

Despite his army gaining a great deal of strength they were defeated. Zero only appearing after the Super Saiyan 2s were weakened, and killed one of them with a sneak attack after their fights against his Elites.

Zero used the full power his true form provided him in order to defeat the Saiyans one by one, commenting that sacrificing his army to tire them out was the correct decision.

He proceeded to torture, mutilate, and kill the Saiyans until he felt a power approaching.

Kaestos had felt his friends Ki disappearing and rushed towards East City.

Zero and one other Saiyan were the only ones alive, and Zero pinning severed corpses around where he was in the city. Zero then hid, waiting for the Saiyan to discover the bodies and wanting to see the horror and despair on his face.

Mathazar was the only one left alive aside from Kaestos, and told him to run; Zero appeared at that moment and blasted Mathazar before taunting Kaestos with how easy it was to kill his friends.

This would prove to be his undoing however, as Kaestos finally managed to ascend and actually entered Super Saiyan 3, far surpassing the Tyrant.

Zero utilized his Super Evolution in an attempt to survive, but found himself horribly outmatched, and was eventually killed by Kaestos after having his body and spirit broken, bringing vengeance to the Saiyans friends and all those he had hurt.

Becoming Ultimate
While in Hell, Zero had no limits on his physical stamina, and trained constantly.

After 6 years he had attained a new form, Ultimate Evolution, and with the immense power it gave him Zero procceded to overthrow the managment of Hell, sending the afterlife into chaos.

Kaestos had been training with Whis at this time, and he was attempting to master his new Saiyan God power to its fullest. Whis informed his student of Zero's actions.

Whis sent the Saiyan to Hell, where the two enemies confronted one another, Zero powered up to his Super Evolution and surprised Kaestos with the tremendous power he had gained, but Zero still wasn't able to equal or even actually damage the Godly Saiyan.

Zero then pulled out his trump card, Ultimate Evolution, which granted him enough power to force Kaestos into his Super Saiyan God form to match his foe.

Kaestos still hadn't mastered his new power entirely, and had great difficulty in his fight against Zero.

During his training however, Zero had neglected to train his new form to utilize less Ki, and be less stressful on his body due to being in Hell.

Kaestos had however, and managed to fight Zero long enough fight that eventually the tyrant lost control over his new power.

Eventually, after about an hour of fighting against his foe, Zero's power was drained and he went back to his True Form, with Kaestos still in Super Saiyan God.

Zero's very existence was now in the hands of the one who hated him the most ,and Kaestos prepared to destroy the monster forever, but was convinced not to by the Z-Warriors that Zero himself had killed.

Despite being spared Kaestos promised Zero that if he stepped out of line one more time he would defeat him again, and next time he won't survive.

Zero was imprisoned again, this time in an inescapable part of Hell, even to one as powerful as him.

Kaestos left Hell and his most hated foe behind; preparing to move on with his life after finally gaining closure with his deceased friends.

Power
As a child Zero held a great deal of power, and was able to assume control of the Galactic Trade Organization from its previous rulers when he was 9 years old.

Zero's power after his preperations for the Invasion of Earth was enough that he could match and defeat 5 tired Super Saiyan 2s, however he admitted that each of them were at much less than half their strength at the time.

After his training and tranfomation into his Super Evolution Zero's power was equal to Kaestos' Super Saiyan 2, but due to his opponent skipping that form and entering Super Saiyan 3 he was killed by the Saiyan.

Zero had no physical stamina limitations in Hell, and trained for 4 years straight eventually gaining a golden power.

While in his Ultimate Evolution he has a normal ki equivalent to God Ki 11, and was able to outmatch Beerus and even Super Saiyan God Kaestos when he was still learning to master his Godly power.

Transformations

 * Final Form - Zero attained mastery of the full power his true form holds at a young age, never having to seal it to remain in control. After training and preparing for his Invasion of Earth this form is slightly more powerful than Mathazar as a Super Saiyan 2 or Kaestos as a Super Saiyan.
 * Super Evolution - In his fight against Kaestos he entered this state which he used in an attempt to deal with the Super Saiyan 3 transformation. Zero is equal to Kaestos' Super Saiyan 2 power in this form.
 * Ultimate Evolution - After his death Zero started training in Hell for years, eventually managing to attain this form after 4 years. In this form Zero gains a tremendous amount of power, and is able to actually surpass Kaestos when he was in Super Saiyan God, albiet he was still learning to master and control his Godly power. This form does have a fatal flaw; Zero never attempted to reduce the strain it puts on his body or Ki due to it seemingly not being an issue as he was dead already. This is what allowed Kaestos to defeat Zero upon the strain catching up with him.

Techniques
Super Death Wave - Zero can use this technique to release a wave of energy, which in his Super Evolution is able to briefly clash against Super Saiyan 3 Kaestos' Shining Blast.

Golden Death Wave -  When Zero is in his Ultimate Evolution he used this attack, which actually overwhelmed a Super Saiyan God Kaestos' Godly Blast, but the Saiyan wasn't finished with his training at the time.

Super Death Bomb - Zero used this technique in an attempt to defeat Kaestos, but was killed before he could use it. Based on its appearance, the power Kaestos felt from it, and Zero's comments it could presumably destroy Earth in one shot.

Golden Death Bomb -  Zero used this attack when fighting Kaestos in the afterlife, and when it was deflected a tremendous amount of damage was done to Hell.

Trivia

 * Zero's name is a reference to the term "Absolute Zero", which is the state at which atoms cease movement entirely and the temperature of something cannot get any lower.