Not much is known about the origin of Tusk other then that he is a member of The Dark Riders, which is a team composed of Inhumans that where kidnapped by Apocalypse. They where brought together in order for them to serve him and by carrying out his "survival of the fittest," idealism by eliminating mutants that were deemed too weak.
Tusk was created by Whilce Portacio, Jim Lee and Chris Claremont and first appeared in the pages of X-Factor Volume 1 issue 65 (1991).
Major Story Arcs
Tusk has been one of the original members of the team and where sent towards Earth in order to infect an infant Nathan Summers with the techno-organic virus. In retaliation, Nathan Summers' father and his team, X-Factor, attacked the Dark Raiders and Apocalypse himself. While Tusk put up a big fight, he and the Dark Riders where eventually defeated. Tusk would encounter Cyclops and Jean Grey again during the X-Cutioners' Song event, but was then not seen or heard from in some time.
Tusk had been present in later incarnations of The Dark Riders. On one such ocassion, Tusk and his teammates abducted the X-Man Wolverine and attempted to infuse adamantium to his skeleton once more. Wolverine however escaped and killed a lot of Tusk's teammates. Unlike others in his group he escaped from Wolverine.
A New Team
After most of his teammembers had died, Tusk faded from the frontlines for some time. However, later he joined a second team of Dark Raiders which was run by Stryfe. He was tasked to fight against Nate Grey, the mutant also known as "X-Man". He was serverly crippled by Nate during their encounter and the team was defeated. His current status is unknown.
Powers and Abilities
He had the power of super strength and resistance. He also created duplicates (much like Madrox) and they sprouted out of the top of his hunched back. These creatures (called Underlings) shared Tusk's strength and invulnerability and could think individually but still had a psychic connection with the main body.
X-Men: The Animated Series
Here he was established as a mutant and not an Inhuman. He appeared on the 4th season episode Secrets, No Longer Buried working as a mechanic in the town of Skull Mesa (curiously mentioning a family and showing a generally friendly demeanor), and coming to the aid of a de-powered Cyclops. In the series final episode he was also seen as a member of Magneto's army.