The classic X-Men villain Apocalypse has given himself a new name. Hailing from ancient Egypt, En Sabah Nur considers himself to be the first mutant. The claim is more testimony to Apocalypse's pride than to historical reality, of course; the earliest-known mutant is Selene, who predates Apocalypse by over 10,000 years. But Apocalypse has never exactly been known for his humility.
Apocalypse has settled on the mutant nation of Krakoa, and he claims to have abandoned his old philosophy of "survival of the fittest." He's reinterpreting his own history, claiming it was all about the desire for a mutant nation and that all his prior atrocities were "in the hopes of mutantdom finally asserting dominance over this world." In his view, Krakoa is the fulfillment of that goal. He's set himself up as a scholarly priest, a change in behavior that nobody exactly finds convincing.
Excalibur #1 reveals that, in support of this new identity, En Sabah Nur has given himself a brand new name. He's basically created a new Krakoan character, analogous to the letter A, and taken that as his name. It's clearly intended to symbolize that the old has gone and that he now lives for Krakoa; but there are also troubling implications. He still seems arrogant enough to create a whole new character in the Krakoan alphabet, suggesting he views himself as beyond definition. Notice also that this is derived from the letter "A," the first letter in the English alphabet, subtly implying how important he considers himself to be.
Apocalypse is reinventing himself, and even using powers that he doesn't normally display - such as a surprising potent psychic ability that he's never shown before. But it's crucial to note that he most certainly has an agenda for being on Krakoa. Excalibur #1 sees Apocalypse manipulate Rogue into using her powers to expose herself to a mystic energy, and frankly it seems to be just what he hoped would happen.
It's worth noting that Apocalypse is more familiar than most with the living island of Krakoa, that the mutant race now call home. Powers of X #4 reveals that he first visited this land millennia ago, when it was called "Okkara." This place was split in half by the Twilight Sword, divided into the yin and yang of Krakoa and Arakko. The event triggered some sort of demonic invasion, and Apocalypse and his first Horsemen were key in driving the creatures back and saving the world. Given Apocalypse's familiarity with Krakoa, and the implication the land has always had ties to magic, everything he's doing right now could be with a very sinister goal in mind.
Excalibur #1 is available now from Marvel Comics.