In a world where the Dragon Balls have lost their power and the Saiyans have disappeared, a new threat emerges. A powerful and mysterious warrior, known only as "Kaiser," appears on Earth, seeking to conquer and destroy all life.

As the battle begins, Kaiser demonstrates incredible strength and speed, pushing Goku to his limits. Just as Goku starts to gain the upper hand, Kaiser reveals his true power: the ability to absorb and assimilate the energy of his opponents.

Trunks, Vegeta, and Piccolo set out to find and defeat Kaiser, but soon realize that he has become much stronger than they anticipated. The trio is defeated, and Kaiser continues his rampage on Earth.

The game begins with Goku, now living a peaceful life on Earth, being interrupted by a sudden and intense ki blast. The blast is revealed to be Kaiser, who has come to challenge Goku and prove his superiority.

The fight ends with Goku being absorbed by Kaiser, who now possesses Goku's power. The Z-Warriors, alerted by the sudden ki explosion, gather to discuss the new threat.

The people of Earth are thrown into chaos as Kaiser begins to wreak havoc on the planet. The Z-Warriors, now disbanded and scattered, must reunite to stop this new menace.