"When Worlds Collide!"
January 2000
Doom's world merges with the FF's; they join him in battling the Dream Celestial
continues in
*
Doom #1
"Doom Without Armor"
October 2000
(10/2000)
Doom arrives powerless on Counter-Earth, and is taken as a slave
reprinted in
*
44 Years of Fantastic Four
2005, in collection
(2005*)