Eric Masterson was working as an architect in New York when he befriended a construction worker called Sigurd Jarlson. He had a son with his wife Marcy Masterson named Kevin, but the two later divorced. The construction site he was working at was attacked by Mongoose, but Spider-Man arrived and drove him away. However, during the fight, Masterson was injured by a falling girder, but Sigurd, who was revealed to be Thor, rushed him to the hospital. Eric was alive but injured and on crutches. Sigurd and Jerry met up with Eric and tag along on a construction bid, but the plant was attacked by Quicksand. Thor was able to transport the plant to a dead world before it could explode. He returned to work with Sigurd and Jerry.
Quicksand and Mongoose attacked again, and Brute Benhurst was given the Bloodaxe, transforming him into the new Executioner. Thor battled this seemingly-returned warrior, but realized that it was not really Skurge when he backhanded young Kevin. Thor unleashed his full might, and defeated him. Mongoose kidnapped Eric to draw Thor out. Thor sensed the trouble through the bond he shared with Kevin's toy hammer. Odin then sent a Negative Zone Portal. When he arrived at Eric's apartment, he was given one word to go on; "Wundagore". Moongoose's master was revealed to be Count Tagar who wanted Thor to bring Hercules and the High Evolutionary back from the Black Galaxy. Thor agreed to help and Eric accompanied him.
In the Black Galaxy they battled strange organisms that Thor recognized as existing inside the Celestial he fought. They make their way to the Null Bomb the Colonizers sent to destroy the Black Galaxy, and Thor redirected the blast. On top of the mountain summit, they discovered another Celestial along with Hercules and the High Evolutionary trapped inside strange containers. A surge of energy builds and they are all witness to the birth of a new Celestial. The Celestial sent them all away, restoring everyone in the process.
Merged With Thor
They returned home, but they were attacked by Mongoose. Eric lifted Mjolnir, but received a fatal blast before he could strike. Hercules managed to drive off Mongoose and Thor plead to Odin to spare Eric. Odin then merged the two, while each retains their unique personalities. Bonded as one they battled Doctor Doom. They faced Juggernaut and Ulik.
Being merged with Thor was ruining Eric's life; he lost his client and his personal life was falling apart. Marcy was determined to reclaim full custody of Kevin at any cost. Eric returned home to find Hercules under the Dweller's control and Susan Austin, his assistant, about to be drained. The Dweller commanded Hercules to defend him and hurled Eric over the balcony. He turned into Thor and helped free his friend, but when they returned to the apartment it was trashed and child services was there. Due to the fight he was not able to pick Kevin up from school, so Marcy did and made sure CPS knew about it. He battled the Wrecking Crew (Earth-616) with Hercules in the hopes of restoring his friend's confidence.
Stellaris came to Earth looking for after the Replicoid, wanting vengeance against the Celestials. Thor and the Avengers fought her off, but not before she killed the Replicoid. Stellaris then set out after another reading of Celestial energy – Hercules. Hercules was alone watching Kevin while Susan and Sam went to meet with Marcy's lawyers. Hercules defeated Stellaris, but Eric came to a monumental decision; he would relinquish custody of his son Kevin to Marcy for his own welfare. Thor and Hercules traveled to the Black Galaxy to find the High Evolutionary. Thor battled Nobilus, who was set free by Stellaris. During the battle, a massive blast caused Eric to be split from Thor. The galaxy became a Celestial. They returned to Asgard after being warned by Sif. They found Surtur and Ymir locked in combat. To defeat them, Thor had to retrieve Twilight from the Sea of Eternal Night. Thor became trapped, and Eric made a fateful sacrifice. He bridged Thor and Mjolnir, remerging with Thor. Thor lit Twilight in the Eternal Flame which causes Odin's control over Surtur to vanish. Surtur and Ymir fight over Twilight, and while they are distracted, Thor transports them both into the Sea of Eternal Night. Back on Earth; Eric and Jackie Lukus go on a date, making Susan jealous. He then had to face Excalibur, who was tricked into thinking he was Juggernaut. With the real one captured, Eric was confronted by Susan and Jerry, who revealed their assumption of his secret; Jerry and Susan thought Eric has a drinking problem. Loki manipulated things to bring Thor, Ghost Rider, and the Wrecking Crew together. Loki wanted to reclaim the Asgardian energy from the Wrecking Crew. Leena consoled Susan and told her how to win Eric. Loki stole the energy from everyone but Wrecker.
Enchantress kidnapped Kevin and brought him to Loki, as he had finished draining the last of the Asgardian sorcery from the Wrecker. Thor battles his way through Ulik and confronts Loki. Amora decides she wants no further part of Loki's plan. Loki demanded Thor relinquish his hammer or he would kill Kevin. Thor battled Loki for the life of Kevin. Code: Blue managed to get Kevin to safety, and Thor beat Loki. The Enchantress didn't want any witnesses, and believed Susan could identify her. Out of spite, Loki sent a mystic blast towards Marcy and Kevin, but Amora caused Susan to dive in front of it, saving them and sacrificing herself. Thor felt that there is no more choice. He began the ancient ritual, and using his lifeforce, killed Loki. For breaking Odin's sacred law, Thor was banished for all eternity. But Thor plead to not leave Earth defenseless and to spare Eric. So Heimdall caused Eric to become the new Thor with all of Thor's powers, but Eric's mind. Eric, as the new "Thor" battled Ulik but was easily beaten. However he returned and fought like himself, instead of trying to fight like the original Thor, and is victorious. Eric visited a comatose Susan, and then Leena came in and whispered to her that she may continue to live as long as she was not a threat. Eric was uneasy in the role, finding it difficult to convince his teammates that he was the same Thor that had accompanied them on previous missions. He eventually admitted the truth.
Thunderstrike was confronted by a new Bloodaxe, who claimed the wielder was someone close to him. It turned out to be his girlfriend, Jackie Lukus. Eric was able to save her and use both his mace and the Bloodaxe to battle Seth, becoming possessed in the process. He died to purge himself of its corruption and refused a place in Valhalla.
His mace was revealed to have been repaired by Thor and left in the custody of the Avengers) was eventually given by Commander Steve Rogers to Kevin, who went on to become the new Thunderstrike.
Thunderstrike was later revived as part of the Grim Reaper's Legion of the Unliving. After overcoming the Grim Reaper's control, he was returned to the spirit world by the Scarlet Witch. It is not made clear if this was Eric that returned, or a magical construct of some sort, although his last words were to Thor in regards to checking on his son Kevin.
- Eric proved himself worthy to wield Mjolnir, and was merged with Thor to save his life. When Odin had Eric replace Thor, Masterson had the full strength and weather control powers as Thor. Later, when Eric wielded the enchanted mace known as Thunderstrike, the mace granted him a number of superhuman attributes, many of which are conventional among the Asgardians:
- Transformation: By tapping the enchanted mace, Masterson transformed from his Thunderstrike form to his mortal form, in which his mace transformed into a cane. By tapping the cane, Masterson was transformed back into his Thunderstrike form and the cane reverted to the mace.
- Superhuman Strength: As Thor, Masterson had Class 100 strength. In his Thunderstrike form, Masterson possessed superhuman strength superior to that of the average Asgardian male, being able to lift about 100 tons. In human form, Eric Masterson had the strength of a normal human who engaged in regular exercise.
- Superhuman Speed: As Thunderstrike, Masterson was capable of running and moving at speeds greater than even the finest human athlete.
- Superhuman Stamina: As Thunderstrike, Masterson's musculature produced considerably less fatigue toxins during physical activity than the musculature of a human being. His physical stamina was equal to that of the average Asgardian male and he could exert himself at peak capacity for about 24 hours before fatigue began to impair him.
- Superhumanly Dense Tissue: As Thunderstrike, Masterson's skin, muscle, and bone tissues had 3 times the density than the same tissue of a human being. This contributed, somewhat, to his superhuman strength and weight.
- Superhuman Durability: As Thunderstrike, Masterson's body was far more resistant to physical injury than the body of an ordinary human. He was capable of withstanding great impact forces, temperature and pressure extremes, and powerful energy blasts without sustaining injury.
- Regenerative Healing Factor: As Thunderstrike, like all Asgardians, if injured, Masterson's body could heal itself with superhuman levels of speed and efficiency. However, he would not have been able to regenerate missing limbs or organs without magical assistance.
- Superhuman Longevity: As Thunderstrike, like all Asgardians, Masterson was highly resistant to the effects of aging resulting in him aging at a rate much slower than a human being, although he was not immortal. However, he was immune to all known Earthly diseases and infections.
- Allspeak: Thanks to the Allspeak, Asgardians can communicate with and be understood by all races.
- Thunderstrike Mace: Named from which he derived his alter ego. Forged out of the mystical metal Uru, enabling it with the chief properties of durability and ability to maintain enchantment. Other than being a nearly indestructible throwing weapon, the mace was augmented by Odin, Lord of Asgard with the following enchantments:
- The first enchantment was by stamping the mace Thunderstrike would revert to his mortal human form, dressed in whichever clothes he last wore in that form, while the mace transformed into a wooden cane.
- The second enchantment was by stamping the cane Eric Masterson turned back into his Asgardian form, bearded and garbed in his Thunderstrike costume, while the cane again became the mace.
- The third enchantment was by throwing the mace and gripping its strap, Thunderstrike could fly at exceptionally high speeds. Also, when trown, the mace will always return to its wielder hands with irresitible force.
- The fourth enchantment was that he could use the mace to project powerful blasts of mystical concussive energy and lightning.
- The fifth enchantment was the mace magically enabled him to survive the adverse conditions of outer space, including its lack of oxygen.
- Thunderstrike could also open portals to anywhere in the universe, even other dimensions.
- The mace presumably had other enchantments as well that Eric had yet to discover at the time of his death.
As Thor or Thunderstrike, Eric could throw the hammer/mace and fly by holding on to the handle.
- 204 appearance(s) of Eric Masterson (Earth-616)
- 18 minor appearance(s) of Eric Masterson (Earth-616)
- 13 mention(s) of Eric Masterson (Earth-616)
- 84 image(s) of Eric Masterson (Earth-616)
- 11 quotation(s) by or about Eric Masterson (Earth-616)
- 3 item(s) used/owned by Eric Masterson (Earth-616)