Tarianna

Tarianna of Leenn was a warrior woman from Battleworld, which was created by the Beyonder to stage the Secret Wars. Leenn was a duplicate of the Latverian capital, Doomstadt and was controlled by the evil Wizard, a giant simulacrum of Doctor Doom. After adventuring with Ben Grimm, The Thing, for some time, it was revealed that Tarianna had no independent existence and was a material projection of Ben's mental image of his ideal woman.

On a side note Tarianna is one of the tallest women in the Marvel Universe. (Not including heroines who can change their size).