J'onn J'onzz was the last Martian and one of the founding members of the Justice League. J'onn can be seen as the true founder of the Justice League, having telepathically reached out to each of the founding members, except for Batman, who nonetheless followed Superman's lead, and gathered them together. 

J'onn J'onzz
Vital statistics
Aliases Martian Manhunter
Birthplace Mars
Date of Birth Unknown
Age Unknown
Family Unknown
Affiliations Unknown
Alignment Unknown
Species Martian
Occupation Unknown
Rank Unknown
Abilities Superhuman strength, speed, and stamina

Limited Invulnerability Flight Telepathy Density Control Regeneration Shapeshifting Longevity

Power Level 140,000,000
Weapons Unknown
Unique Trait Unknown
Goal Unknown
First Appearance Unknown
Voice Actor Carl Lumbly (FUNimation Dub & Saban Dub)
Seiyū Seiji Sasaki