Timeskip

After gohan adopted leo as his grandson he also began teaching him martial arts only basics because he thought that it will not be good for his growth doing hard exercises even though leo said that he will be fine because of his saiyan physique.

Leo also tried to sense ki in the surroundings to learn how to control ki and he became successful in sensing because of his bloodline being highest. He started to manipulate it and do kamehameha and failed because he didn't know how to perform a kamehameha and thought because he didn't see it in real life so he can't perform it.

Goku performed kamehameha though only seeing it once performed by master roshi when he tried to put down the flames of ox king's castle. So leo asked gohan to teach him some ki techniques and gohan rejected it saying first he needed to practice martial arts then only he can practice it because it requires a sturdy body and calm mind to perform which only martial artists can do.

After some pleading gohan said that he will perform it only once and then he should practice martial arts and only when he approves he should practice because if one can't control ki properly it will either damage his internal organs or he will his hands when trying to control it.

Gohan : Watch it closely leo, this is the highest technique my master has teached me and it is called kamehameha.

Leo : Kamehameha?

Gohan : Yes kamehameha. First you have to rotate ki in your hands like a wheel and then release it.(Sorry if this is not the correct explanation of it)

Then starts performing ka me ha me ha and a blue ray came out of gohan's hands and it destroyed the tree where the beam hit it. Leo thought for a second and in his mind he is watching how gogan performed ka me ha me ha and he remembered it.

He done the same posture like gohan and starts to perform ka me ha me ha and then a blue beam came out of leo's hands and it is bigger than gohan's beam and it destroyed the front area of him.

Gohan becaame shocked because the greatest technique of his teacher's was easily done by a 6 year old kid and saw the destruction he cause with that. He then proceeds to tell leo that he can't use ka me ha me ha unless he perfectly controls ki.

Leo came out of his thoughts by gohan's warning and he also reminded to first practice ki control because if there is a living being it will be vapourized due to the heat of that energy. Leo then starts practicing martial arts with his grandpa during the day time and in nights he meditates to practice ki control.

**Time Skip to 9 years**

On a sunny day in the training grounds you can see two kids fighting each other. They are the two saiyans Son Leo and Son Goku and they are sparring against each other and then their grandpa gohan called them for lunch.

Leo and goku sat and started to devour the food like hungry beasts and leo thought that so many things happened in these 9 years.

On First year Leo trained with gohan for martial arts and his ki control got better after one month of training. Now he can control his ki beam and can control how much damage he wants to cause. Gohan also started teaching him how to do kikoha(Ki blasts).

On middle of second year goku saw them doing training and also asked his grandpa to train him and gohan agreed because his old bones can't keep up with his grandson in training and he started teaching him too.

In this timeline leo didn't want his grandpa to die because some closer to him in those years of training so he asks gohan when there is a full moon and inform one day prior to him and when gohan asked why leo said that when saiyans(with tails) see full moon they transform into a great ape and destroy everything.

He said that he can control his great ape form(because god said that he won't go berserk due to his primordial bloodline) and goku can't control it and he will end up destroy the whole forest.

To control his form better he got out on a full moon day and when he saw the full moon he starts to transform into a great and some powerful people can sense leo's power because his battle power is greater than 1 million and he gained control of it.

Gohan became shocked and asked leo whethe he can control his form and he even talked in his ape form and said that he is fine and he starts to condense the oozaru form to negate the drawbacks of it being big.

He calmed down and started to shrink his size and now he became a great ape of human size and leo thought it is more comfortable than a human and because he didn't want to permanently live as a animal and thought of trabsforming back to human and transferred back to his human form.

And like that remaining years passed and goku always sparred with leo and learned how to control his ki also goku became stronger than the canon version and leo can easily kill vegeta even in his ape when he fought with goku in canon.

He also went to train with master roshi 1 year because gohan teached him what he is capable of and when he told about his teacher muten roshi to leo, leo asked he wanted to go and train with him and he will be back after training.

Leo : Grandpa where is this master roshi you are talking about lives?

Gohan : You just have to flt straight to east and tou will find a small island and that is where he lives.

(He also learned how to fly by manipulating ki)

Then leo went to master roshi and started training under him. Roshi accepted him because his disciple said that he is his grandson and a martial arts prodigy and also said that the power they felt before was him and roshi started teaching him.

In only 2 months he learned everything from master roshi and he sparred with him everyday for next four months and he also learned observation haki. Because of his battle power being high he only spar only using martial arts and not his strength because he can easily break master roshi bones and accidentally kill him.

He used being blindfold in his spars to train his six senses and he can also do observation haki after his training done with roshi. He is at peak of intermediate level of observation haki. He can't break through that because he felt that he needed a great fight to simulate his senses to higher level.

He came back before 6 months canon starts and also spar with goku daily and also teach him how to do kikoha.

Goku Power Level - 200

Leo Power Level - 15,000,000

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