Grant Morrison is the metatextual representation of the author, Grant Morrison. He was created as a means by which Morrison could personally interact with his own characters and address the audience.
Insofar as he can be described as having been created, Grant Morrison was created by Grant Morrison and Charles Truog. He made his first fictional appearance in Animal Man #10.
Major Story Arcs
Morrison begins seeding hints throughout Animal Man's life that all is not as it seems. He draws Buddy through Limbo and into the fictional real world, a step removed from the world in which you are currently reading this sentence. He greets Buddy at his door, and invites him into the fictional representation of his own home. He writes a situation in which Buddy kills him in an effort to demonstrate his utter control over this world. He explains that he is responsible for the deaths of Buddy's family, and he and Buddy discuss the nature of reality and the fact that Buddy is technically immortal. He creates some enemies to make the story more interesting to draw, and adds a fight scene to keep the reader's interest. He speaks to you, and thanks his various supporters and co-creators. He reflects on the way that pain and suffering is twisted into our entertainment, before returning Buddy to his home reality, with no memory of their meeting. He walks alone by the river and remembers an imaginary friend from his childhood named Foxy to whom he used to signal. In this reality, which is not reality, his imaginary friend signals back.
The Writer, now entrapped in the comic book continuity as a consequence of his own creation, mysteriously recruits himself to join the Suicide Squad. Distressed by the fact that other writers can now control his fate, he nonetheless accompanies the group on a mission. He successfully wields his control of the script to defeat several enemies, but suffers from a sudden case of writer's block. He is then attacked and killed by a werebeast.
Powers and Abilities
Grant Morrison is the author, and is thus technically omnipotent and omniscient in the comic book universe. While being written by other authors, he has displayed an awareness of his own fictional nature, access to the physical script for the issue allowing a limited prescience, and a reality manipulation ability that allows him to cause anything to happen once he has written it into the script.
Weapons and Equipment
The Writer occasionally carries a small computer on which he can observe and contribute to the script for the issue in which he appears. However, if he is not the author events will continue to occur even if he stops writing.