Ultraman Story 0
Like the other Ultras in their series Jack was once a humanoid being from the planet that would be called the Land of Light. When the Plasma Sun was activated Jack was transformed like the rest of his people and fought the various monsters that also appeared. He also witnessed the appearance of the Baltans' ships and the declaration towards galactic conquest. With the other Ultra Brothers he went out into space to assess the effects the Plasma Sun's light had on the universe and combat the monsters that appeared as a result.
One a distant planet, many years later, Jack fought in the ocean against three sea monsters simultaneously. Pressed for time, Jack forsook the advice of Father of Ultra who warned him about his Color Timer. Even though they are Ultras, they are not god-like. As a consequence, Jack, though defeating the monsters, had his transformation device shattered. He was rescued from drowning by a merman-like alien.
Prior to his battle with the sea monsters, Jack used a bracelet like Zoffy's to transform. It presumably worked in a similar fashion to his, an item bearing plasma ore. However after his transformation item's destruction, Jack's Plasma Ore became a part of him allowing him to transform at will the same way Hideki Go does in the TV series.
- Specium Ray: The standard basic Ultra Beam, can destroy monsters in one shot.
- Meteor Kick: An extremely powerful kick skywards that can easily pierce through an enemy. First used in Volume 2.
- Combined Specium Ray : Used with Ultraman when the former's left and Jack's right wrists were incapacitated, by overlapping their good arms in the cross shape to obliterate the abomination made by Alien Guts. Used in Volume 11.
- Ultra Tornado: Used with Ultraman to destroy the artificial monsters made by the leader of the Land of Fire in Volume 11. This technique uses up a lot of energy.
- Unlike his original counterpart, this Jack had a transformation item like the other Ultras, a bracelet. But once it broke, Jack transforms again by force of will, like Hideki Go did.
- Jack also demonstrated what was previously only implied, that the people of the Land of Light had extended life spans, having been in human form long enough to see one of the Aquatic Homids he met as a boy, to die from old age, yet his appearance did not change.