When the Celestials were casting final judgement on the planet Pangonia the brave Asgardian warrior Thor sought to intervene and while his assault only cause the Celestials annoyance the formidable Exitar the Executioner saw the valor of the great warrior and produce a replica of him within minutes empowered it with the Celestial lifeforce. The replica came to Thor and restored his destroy hammer Mjolnir and teleported him out the planet not before telling Thor to no further intervene in his masters plans.
Later the replica would give a message to Hercules and Thor from the Celestials. It was during this time he took the names Sigurd Jarlson the name Thor had once taken, however Thor now in his guise of Eric Masterson. Eric transformed into Thor at once Replicoid demanded he be given Hercules for he was spreading forbidden information of the Black Galaxy and birth of the possible Celestial. However before anything could get done he was attacked by Stellaris seeking to slay him for he was creation of the Celestials and she hated all things related to them.
While Replicoid came unharmed from the attacks of Stellaris, the replica fear that the Celestial hater would attack Thor because of his past involvements with the Celestials and instead chose to sacrifice it life to appease her.
Replicoid possess all the powers of Thor however do the lack of Mjolnir Thor's legendary weapon he was instead empowered with the Celestial lifeforce this allowed him to change shape, teleport himself and others across vast places, it could fly even in space requiring no air or food, it searched for those who knew of his masters and even reconstruct Thor's mystic hammer with ease.