The Unnamed Species

At the dawn of the last Ice Age, the unknown race sought to escape the deadly cold by putting in place various "time capsules" of sorts, containing themselves perfectly preserved using cryogenics. One of these creatures, later to be given the name of "His Eminence" by various humans, was one of two chosen to reawaken the race, the other died upon awakening due to a unforeseen malfunction. The unnamed creature gave the two members the mark to give to the first people he saw, which "His Eminence" later gave to the four A Nigma High students Finnwich, Elizabeth Mann, Art Wurst and Ping, and made the four work for him. The four students would go onto found the world's most powerful company and would gather the world's best and brightest minds, vast wealth, and the most advanced technology all towards the purpose of finding a way to reopen the Antiquis Triangulum, which "His Eminence" had previously resided in.

Members of the unknown race are last seen in the series' final episode, Date With Destiny. At the end of the episode, legions of the unknown race appear to have been awoken by one Council member who got trapped inside the Pyramid as it exploded.

Trivia

 * Judging by their appearance, they seem to be of reptilian origin, hinting at being a previous evolution, yet much more advanced, of the Tatzelwurm species.
 * However, their reptilian origin could hint at them being an advanced species of dinosaur.
 * The species could possibly be evolved the same way as humans, due to their similar abilities to adapt and learn.
 * There is also a possibility that "His Eminence" and his species is not of earthly origin, and the Antiquis Triangulum could be their means of extraterrestrial travel.