Appearing in "What Is Ultimate X?"
- Karen Grant's group (First appearance)
- Sonny Chiba (Referenced)
- X-Men (Referenced)
- Captain America (Steve Rogers) (Poster)
- The Thing (Ben Grimm) (Poster)
- Magneto (Erik Lensherr) (Referenced)
- S.H.I.E.L.D. (Mentioned)
- Scarlet Witch (Wanda Lensherr) (Illusion or holographic simulation) (Apparently alive)
- Rogue (Marian Carlyle) (Cameo)
- Colossus (Piotr Rasputin) (Cameo)
- Storm (Ororo Munroe) (Cameo)
- Spiral (Cameo)
- Havok (Alex Summers) (Cameo)
Races and Species:
- Mutant Registration Act (Mentioned)
Synopsis for "What Is Ultimate X?"
- Synopsis not yet written
And now...THE HULK?! What impossible situation has the cast of Ultimate X reaching out to the most powerful and dangerous person in the Ultimate Universe? Can The Hulk be controlled or will he smash them all? The senses -shattering conclusion of the first arc of the critically acclaimed series is brought to you by Eisner award winning writer Jeph Loeb and master illustrator Arthur Adams!