Heroic Age
ヒロイック・エイジ (original)
Long ago, the advanced Tribe of Gold vanished from the vast universe. In the void left by their departure, the tyrannical Tribe of Silver ascended to rule, forcing mankind – the Iron Tribe – to the brink of extinction. Now humanity wanders the cosmos in search of a savior. Prophesy has foretold of one who will labor for their freedoms, and on a planet of ruin, a champion is found. A feral boy named Age holds the destiny of their species in his hands and the untold power of the Tribe of Hero within.
Starring Chihiro Suzuki, Ami Koshimizu, Daisuke Kishio, Hiroyuki Yoshino, Miyuki Sawashiro, Susumu Chiba, Yoshinori Fujita, Yui Ishikawa, Yukari Tamura, Takashi Kondo
Watch "Heroic Age" on Hulu Plus released in 2007. It's a animation and action & adventure show, and has a rating of 7.1 out of 10 from Imdb which is usually fine for this kind of show.