X-Men, Vol. 1 Annual #7/1998 A

Doom Quest
Several years ago, Seer, a man with precognitive and psionic abilities working for Doctor Doom, has a vision of an extremely powerful being known as the Onslaught. The always power-hungry Doom wishes to learn more about this almighty creature, hoping he may be able to harness its power. Having discerned a similarity between Onslaught and Magneto, the villain who recently made his public debut, he decides to pry further. With his machines, he and Seer begin making time-jumps, first to the past and then to the future, to find out the circumstances leading to the birth of Onslaught. After Seer mentally establishes a connection with Magneto, he and Doom begin tracking him down in significant events across the years. After several travels across time which prove fruitless, Seer has a brief encounter with Onslaught in the astral plane and discerns traces of Professor X’s psyche in the entity. He suggests they should track down Professor X, rather than Magneto, in order to solve the Onslaught mystery. After a few more time-jumps, they finally arrive at the pivotal moment in which Professor X shut down Magneto’s mind. Doom and Seer both witness the birth of the evil known as the Onslaught. However, as Doom attempts to siphon its power, the Onslaught entity fights back and yanks them back to their proper timeline. Despite failing in his mission, Doom relishes in his knowledge of the future and slays Seer, unwilling to share the power that comes with this knowledge.
Release Date: 1998