Instructions
Avoid standing close to Nappa. Nappa has powerful attack moves but he must be close to hit you with them. Use the Solar Flare move by pressing back and the "Ki Blast" buttons simultaneously to blind Nappa when he is close, giving you time to move away while he is stunned.
Use the Kamehameha by pressing forward and the "Ki Blast" buttons simultaneously. This move shoots a large blue energy blast at Nappa, damaging him from a long distance.
Perform a Solar Flare on Nappa to stun him, following it up with a combo -- a string of attacks in rapid succession. Some combos for Krillin include pressing the "Rush" button five times or pressing the "Rush" button three times followed by the "Smash" button.
Press up and the "Ki Blast" button simultaneously to perform an Ultimate Attack. Ultimate Attacks require three, four or five Ki bars to use. The attack varies depending on the amount of Ki bars used. However, all Ultimate Attacks damage Nappa significantly.
Press the "Aura Spark" button when your Ki meter, located in the lower left corner of the screen, is full. Krillin receives extra power for all of his attacks, allowing him to cause extra damage to Nappa.
Damage Nappa until his health bar, located in the upper right corner of the screen, is empty. Once his health bar is emptied, he is defeated and you have beaten the level.