The lynch pin of Jack Kirby's magnum opus, Fourth World saga was DC Comics The New Gods #1 which appeared in February 1971. Encompassing The Forever People, Mister Miracle, and strangely enough Superman's Pal, Jimmy Olsen; The New Gods presented adventures of the warring citizens of the planets New Genesis and Apokolips who call themselves Gods and live outside of normal time and space in a realm called the Fourth World. These New Gods have evolved due to their close proximity to the Source (a primeval form of energy), believed to be one of the ultimate foundations of the universal expression of energy. Along with their superior technology, genetic stability and evolutionary perfection, the denizens of New Genesis and Apokolips are immortal, stronger, faster, and smarter than humans, despite their resemblance.
New Genesis and Apokolips were originally part of the same world [a planet called Urgrund] which was split apart millennia ago following the death of the old gods during Ragnarok. New Genesis is an idyllic world with unspoiled forests, mountains, and rivers which is governed by the benevolent Highfather, while Apokolips is a nightmarish, ruined dystopia filled with machinery and massive fire pits which is ruled by the tyrannic Darkseid.
The New Gods are vulnerable to an unknown substance called Radion whose effects are toxic in sustained amounts or after explosive exposure. The average New God can even be slain by an application of Radion from a blaster or bomb.
The most prominent character of the New Gods rather large cast was Orion, the second son of Darkseid and half brother of Kalibak whose fighting skill and stamina have earned him the nickname "The Dog of War". As the result of a treaty between the two worlds, Orion was raised as the son of Highfather, where he was taught to control his anger, not an easy task given that his heritage boiled with the rage of the brutal and merciless Darkseid. Learning how to control this dark nature consumed much of Orion's youth, but friends among the New Gods (such as Metron & Lightray) helped him redirect his anger and he became the most powerful warrior either world had ever known.
[There is even more Jack Kirby goodness to come, as a single week is insufficient to encompass the entirety of the King of Comics 1970's output. Up next: Omac!]