Each DragonBall has a different mission you need to complete to get the ball. For each ball you also get $150. Once you have all 7 DragonBalls you can call the Eternal Dragon.(Wish you can either get any attack, Teck, ability, item, or go up one level in the transform (HP gose up but attacks stay same))

1 Star Ball:
You must defeat the T-rex destroying Capsule Corp.
T-Rex
PL:600
Item: 1 Star DB
Attacks: mouthblast-350
HandtoHand: punch-30,kick-50
Dinosaur
Evil

2 Star Ball:
Learn Ultamate Kamehameha

3 Star Ball:
King Cold is terorizing Earth! He must be stopped.

King Cold(KiHiddenForm)
PL:900
Item: 3 Star DB
Attacks: beam cannon-200, renzuko-240, ki blast-100
HandToHand: punch-80, kick-75
Changling
Evil

4 Star Ball:
Freiza is rather upset that you destroyed his father. Now he wants to deatroy Namek! He has sent his most powerful hanchman to destroy the the planet. It's up to you to stop him.

Zarbon(Change 1)
PL:1,500
Item: 4 Star DB
Attacks: lightning strike-525, masenko-360,ki blast-300
HandToHand: punch-120,kick-145
Changling
Evil

5 Star Ball:
It seems Zarbon was unworthy. Freiza is coming to destroy you himself! This may get ugly.

Freiza(Change 3)
PL:2,700
Attacks: death ball-900, energy disk-585, ki blast-445
HandToHand: punch-210, kick-160
Changling
Evil

6 Star Ball:
You thought you destroyed Freiza, but somehow he is still alive! How could this be!? You'll need to fight him again, but watchout, he's even more powerful thatn before.

Frieza(ImperfectForm)
PL:3,990
Attacks: death ball-950, energy disk-600, ki blast-500
HandToHand: punch-325, kick-230
Changling
Evil

7 Star Ball:
Time to get the last DragonBall!, but it's a doosy. Krillin destroyed the remote to shut down the androids and Cell absorbed 18, becoming complete!!! His new power is emence! It's up to you to stop him.

Cell(Perfect Form)
PL:6,575
Attacks: ultamate kamehameha-1,500, energy disk-775, final flash-700, gallet gun-625
HandToHand: punch-425, kick-460
Android
Evil

That's amazing! You accually beat Cell! You definatelly deserve the DragonBalls. You may call the Eternal Dragon and make your wish now.