Dragon Ball Z: Dead Zone

The movie features the villain, Garlic Jr., who is on a vengeful quest to become Guardian of Earth. In order to have his wish fulfilled, his servants kidnap Goku's son Gohan to get the Dragon Ball he is carrying. Garlic Jr. then summons Shenron using the Dragon Balls and wishes for eternal life. Goku must combine forces with his archrival Piccolo Jr. in order to save the world. With Piccolo's, and later Krillin's, help, Goku is able to defeat Garlic Jr.'s evil servants and rescue Gohan.

Kami, feeling responsible for Garlic Jr., arrives and confronts him. However, he is unable to defeat him, and in a last ditch effort Kami decides to sacrifice himself to kill Garlic Jr. However, Piccolo and Goku arrive in time to take on Garlic Jr., but after a long hard battle, they find themselves defeated and exhausted. Garlic Jr. opens a Dead Zone portal in order to trap everyone within.

With time running out, and with the Earth moments away from being sucked into oblivion, Goku realizes that the massive dormant power that lies within his four year old son is Earth's last hope against Garlic Jr.'s Dead Zone. Gohan's hidden power appears, and he sends Garlic Jr. into the portal, trapping him inside, and saving the planet.

In my opinion this is cool