Nappa had fired his Kapa Beam from his mouth and the beam was heading straight for Gohan. At the tender age of five, Gohan thought he was about to die. Mr. Piccolo would change that. The son of the Demon King Piccolo sacrificing himself to save the life of the child of his mortal enemy. Gohan watched in horror as the one who had been a father figure for him for around a year was seemingly dying right in front of him. He heard his blood-curdling screaming as Nappa's energy wave hit Piccolo dead-on. Piccolo stumbled to the ground and struggled out his last words to Gohan, thanking him for being his first and only friend in life. After he finished, he died.
"Mr... Piccolo...?" Gohan whimpers.
"Wake up...Mr Piccolo...please..." he struggles.
He shakes Piccolo's corpse.
"No...Mr. Piccolo...No..." He crys.
"No...No!...No!!!!" Gohan screams.
"I won't let you get away with this!!" he bellows at the top of his lungs.
He starts just screaming. No words, just the sound of his voice.
Gohan just stood in place, grunting in peril, pain, agony and aggravation, gritting his teeth to the point they almost cracked with fists clenched. It was when he was doing this that Krillin noticed something. Gohan's hair was turning gold. This isn't something that Goku ever did, let alone that Raditz or these other Saiyans. 'What is this transformation?' Krillin thought.
"You...hurt...Mr. Piccolo!!" Gohan screams, as a massive burst of energy coming from Gohan makes everyone squint their eyes. Dust makes Gohan unseeable for the time being. The two saiyans are confused as to what the hell just happened. They just saw bright energy come from a toddler. 'What is going on?' Nappa thinks.
The dust settles and Gohan's aura had turned golden. They saw Gohan. His hair was golden, his eyes were green, a calm green, and his clothes were brighter.
"What kind of trick are you playing, brat?" Vegeta mocks.
"You hurt Mr. Piccolo and I will never forgive you!" Gohan cries.
"Vegeta! What does the scouter say about his power level?" Nappa asks. As Gohan had changed his appearance, Nappa was wondering if this was some sort of power boosting transformation or technique. Vegeta puts on his scouter and scans Gohan. The reading shook him to the core. Shakily, Vegeta states that:
"It...It's 76,000...!"
"76,000?! There is no way in hell that that reading is right!" Nappa cries.
"Surely...you're not it. Surely you're not the legend." says Vegeta.
"What do you mean legend-"
"No. You're not thinking that this brat is the legendary Super Saiyan?"
"You cannot be! I am the prince of all Saiyans! I am a Saiyan elite! Being the legendary Super Saiyan is my birthright! I will not stand for this!" Vegeta screams.
"Your little Namekian friend will be toiling in hell!" Vegeta states.
"Don't insult Mr. Piccolo!!!" Gohan screams as he rushes to Vegeta, punching him in the stomach. Vegeta was in maddening agony. The 'fight' begins between Vegeta and a now Super Saiyan Gohan and they proceed to go into the skies. Gohan proceeds to swing a massive flurry of punches in the direction of Vegeta and there was nothing Vegeta could do to stop this. He was being outclassed by a five year old, he was being humiliated by a five year old half-saiyan. Gohan smashes Vegeta's head, sending him flying into the ground below.
Nappa was very understandably shocked. The Saiyan Prince Vegeta was being completely decimated by a half breed saiyan toddler. Perhaps, he thought, Vegeta was nowhere near as strong as everyone thought he was.
"Masenko HA!" Gohan screams as he shoots a Masenko at Vegeta. Vegeta manages to avoid getting killed by the blast, but not entirely missing it. His left arm is destroyed by this gigalith of an energy attack. Vegeta bellows.
"You bastard!! I will destroy your entire planet!" Vegeta screams, while being in inconceivable pain.
Vegeta was hell bent on the destruction of Earth. He would not take this 'utter humiliation and strife' any longer. He was going to wipe every single one of those inferior beings off the face of the planet.