Origin
Tarianna of Leenn was a warrior woman from Battleworld, which was created by the Beyonder to stage the Secret Wars.
Creation
Tarianna was created by John Byrne (writer) and Ron Wilson (artist) and first appeared in The Thing issue 12 (1984).
Major Story Arcs
Battleworld
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).