The Birth: Ahab real name is Rory Campbell and he made his entrance as Ahab in Fantastic Four Annual #23.

The Legend: Ahab is the master of the mutant hounds in the "Days of Future Past" timeline that the X-Men have struggled to stop for years. He hates mutants with a passion, and wants nothing more than to hunt them down and kill them, or break their spirits and turn them into hounds themselves. It should be noted that Ahab was probably screwed up in the head even before Rachel Summers crippled him, necessitating a need for a cyborg body.
When Ahab arrived in the 20th century gunning for the time lost Franklin Richards, he battled The Fantastic Four, New Mutants, X-Factor, and some of the X-Men. He came very close to killing them all. He also encountered Excalibur in his own time, but fled after it became clear that Rachel Summers was no longer afraid of him.
Ahab's hounds all followed him to the letter, as he brainwashed them to do so. The Sentinels of his time tolerated him as well, until they were "reprogrammed." As Rory Campbell, if Ahab really is Rory Campbell, he was good friends with members of Excalibur and had a "crush" on Rachel Summers. This crush turned into a warped obsession when he became Ahab.

Ahab can toss around powerful energy harpoons that are attached to his own life force. Anyone it hits it can kill or seriously injure, and anyone who attempts to grab a harpoon gets burned.
Ahab has technology created by himself that can turn anyone, mutants or otherwise, into brainwashed hounds that serve him willingly. Also, the Sentinels in Ahab's time supplied him with time travel equipment to prevent anyone from messing with the "natural flow" of history.

Literature by Bobby Coakley