What do you get when you combine a person with huge amounts of stamina to an attack, that's magnitude is proportional to the persons stamina; I think you'll find out.
Deep breath, breath out, breath in, breathes out, breathe in, and fire.
Goku thrust his palm forward in the direction of the boulder; a fair sized hole appeared in its center. The blue energy shining on Goku's palm faded and he fell to his knees. He was exalted by his success; he was steadily getting better and better. He sat on the ground then got up and tried again, he kept it up for a few hours before he was too drained to continue, he fell into a slumbering heap on the ground and stayed that way for some time, this was his sixth day, and he was sure as heck making serious progress. When he got up he took a bath in one of the ice cold mountain streams to wash away any lingering traces of laziness. He then started his usual round of duties, the old man had not asked for anything in return for tutoring other than that he dedicate himself and help out with the chores. Of course neither of these was a problem for Goku. Goku sped around the temple, lifting things here and there, breaking things that needed to be broken and transporting things, basically things that took more physical attribution that mental acuity.
Then Goku would climb to his training place again and resume his training. After 2 weeks had passed the old man visited once more and spoke:
"So I believe you have gotten far enough that now you deserve me personal attention, in fact I believe that your capabilities exceed mine" Goku could not help but smile at this, he thought right, how he knew this though was beyond him. "Are you surprised I know this? Well these 2 eyes aren't the only ones I see with you know." Now Goku was impressed, there was another skill for him to learn from the old man, this hope was dashed with the next sentence. "However this is something that I cannot teach you, for your only teacher shall be experience, now let us begin."
However the old man just stood there, waiting. So Goku made the first move, he charged forward, rushing towards the teacher, just before he reached him he jumped a dozen feet into the air and immediately threw a ball of charged blue energy at him. It reached the man at the same time he reached the ground, the teacher raised his hand over his head as if to catch it but just before it reached him it exploded into a wave of rapidly fading energy. So Goku gave it another run, he ran towards the old man and catapulted over him landing behind him, he charged some ki in his hands before throwing it backwards. The old man moved with surprising agility, he moved a few feet ahead and threw his own ball of energy at Goku's one neutralizing it. Then he put the two fingers of his left on the earth and the two of his right on his temple, his right hand started glowing with red energy and the one on the ground glowed with green energy. He made no further move so Goku ran towards him attempting another such attack but from closer range, however before he could reach him an invisible force threw him backwards. The old man smiled.
Goku tried something else, he charged some ki in both his right and left hand, he joined them together and threw the resulting bomb at the old man, but a large rock broke itself from the earth and blocked Goku's attack causing it to denote too soon. Goku tried a few other such moves with the same frustrating result. Goku tried to catch a minute for rest but before he could take a good couple of breaths, strong blasts of energy started coming his way and he was too preoccupied with dodging them to come up with a good strategy, then an idea occurred to him, a test of wills, of stamina.
He joined his hands together and charged them with as much energy as he could while still dodging the torpedo's of energy, they were getting weaker, it was a good sign, it meant that the teacher was tiring. Then he fired, the torpedo's immediately stopped as all of the old man's focus was now riveted on blocking him, however he could not do so, his strength only came so far, his stamina ended and he collapsed on the ground, he stared at his impending doom, thinking that he would finally make amends for his crime, until Goku appeared in front of him and blocked his own attack. He helped the old man up and took him to his private quarters.
"There is nothing more I can teach you my boy, you have surpassed me, now you must continue your journey, let the forces of nature strengthen you and polish your skills, good luck my boy, you were the best student I could ever have hoped to train."
Goku left and to this day wonders why the man was so willing to train him, little does he know, as he was too young to make memories at that time, that this was the same man who had first laid eyes on him on his arrival to this planet. The old man had trained him in hopes that he could atone for his sin of abandoning the child. Neither had the old man nor Goku recognized the other, but as Goku walked away, he could not shake off the feeling that he was leaving something behind.
Bit too dramatic? I just felt the ending was a good twist for this little story of mine, be sure to reviewJ.