In the Age of Apocalypse, the Eternal One’s first known Horsemen staged an attack on the Cape Citadel military base. His fellow Externals Candra and Gideon were joined by the mercenary Sabretooth, plus versions of War and Death. This War could project explosive blasts from his hands, and may therefore have been the counterpart of Abraham Kieros, though this wasn’t confirmed. He was beaten by a combination attack by Iceman and Colossus, two of Magneto’s original X-Men.
In Mutant X, Warren Worthington III was known as the Fallen, and left his teammates in the Six to return to Apocalypse’s Horsemen. Famine and Pestilence did not appear to be familiar characters in this reality, but War appeared similar enough to Abraham Lincoln Kieros that he may have been a counterpart of him.