Major Story Arcs
Devil by the Deed
Hunter Rose, the original Grendel, is killed by Argent, his werewolf archenemy.
Three years after his death, the skull and partial skeleton of Hunter Rose (which had been dissected by scientists) is included in a museum exhibition called Gotham City Killers. Grendel Prime is sent from the future to get it and use it for mystic purposes (as explained below under Devil Quest). However, Grendel Prime is stopped by Batman, and Robin manages to shoot the skull out of Grendel Prime's hands with a grappling arrow, which creates a large hole in the forehead.
Four Devils, One Hell
Renute, the (secretly) vampire leader of the New Orleans Grendel krewe, hears a voodoo prophecy that whoever is the heir of Charlemagne on the 800th anniversary of Hunter Rose's death will become the heir of Hunter Rose. Renute has come to hate everything about Grendel, and decides to amass all the important Grendel relics and treasures he can, so he can then destroy them with an atom bomb. This includes both the original skull of Hunter Rose (which still has the hole in the forehead, and is now missing its jaw) and his putative reincarnation.
However, a rogue and insane Grendel named Alfred Bixby, who believes himself to be a knight of Charlemagne, has a vision of the skull, and believes he has been charged with saving it. He travels to New Orleans in a quest to do just that.
Renute captures Bixby and some other troublemakers and tells them about his plan, showing them the skull and the young boy who will become Rose's reincarnation. However, Bixby and the others escape and attack Renute and his minions. Bixby finally lays his hands on the "holy" skull, but then throws it at the head of Dulac, one of Renute's chief warriors. This smashes the skull into pieces and kills Dulac. Renute is eventually defeated.
The shards of the skull and the rest of Rose's skeleton are then transported to the archives of Orion Assante, the benevolent Grendel-Khan.
Centuries later, a fragment of the "true skull," as it is now called, comes into the hands of Grendel-Prime and Dr. Creach. They use it to create a "meat machine" that picks up on necronovas, or the mental energy that is released through death. They want to use it to communicate with the dead; Prime wants to communicate with Hunter Rose's spirit in particular, so that he can reconnect with the true meaning of Grendel. However, the Session Twins, who are trying to find Grendel-Prime for the current weak Grendel-Khan, Jupiter III, break in at just the wrong time and shoot the machine, sending Grendel-Prime back in time (to Batman/Grendel II, above) instead of having him communicate with the soul of Hunter Rose. Apparently Grendel-Prime is sent to the era of Batman because he is mystically attracted to Rose's skull, which is on display there.
Hitchcock Blue arrives on the scene a short time after. Everyone else has left. He finds the fragment of the skull and brings it along with him on his travels home. At one point he runs into a man on an island and tells him his story, then throws the skull piece away in frustration. Hitchcock Blue leaves. A few minutes later, Grendel-Prime mystically appears again from the past, coming out of the skull fragment. He drives away on the other man's bike and leaves the skull fragment on the ground.