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Quote1 Jack of Hearts, the novice super-hero -- is still around! Quote2
Jack of Hearts[src]


Early Life[]

Jonathan Hart (Earth-616) from Marvel Zombies Supreme Vol 1 4 0003

Arguing with his card game obsessed father.

Jack Hart was the son of Dr. Phillip Hart, a brilliant scientist who developed a revolutionary, extremely efficient liquid fuel called "Zero Fluid", and a humanoid alien woman of the Contraxian race. The alien was one of many scientists dispatched to try to discover an energy source to resuscitate the dwindling nuclear processes of the Contraxian sun. Learning of Hart's experiments, the alien assumed a totally human form to keep Hart under surveillance. Hart and the alien eventually met, married, and produced a son they named Jack. The alien woman, "Marie", died in a car accident when the boy was a child. Jack grew up without knowing of his mother's origins.[6]

Jonathan Hart (Earth-616) from Marvel Zombies Supreme Vol 1 4 0001

Doused with Zero Fluid

When Jack was a teenager, Phillip Hart perfected his "Zero Fluid" and decided to donate the fuel to all the free countries of the world. Hart was then contacted by agents of the criminal Corporation who wanted to market the Zero Fluid. Refusing to deal with them, Phillip Hart was murdered by Corporation agents before the eyes of his son.[7]

Jonathan Hart (Earth-616) from Marvel Zombies Supreme Vol 1 4 0002

Explosive new powers

Managing to escape, Jack Hart took refuge in his father's basement laboratory Corporation agents broke in minutes later, and their laser-cannon sheared through the laboratory door, striking the vat of Zero Fluid. Doused by the powerful, corrosive fuel, Hart underwent a mutagenic change and began to glow. With an uncontrollable burst of energy generated by his entire body, Hart killed his father's murderers. Vowing vengeance on the entire Corporation, Hart fashioned a costume for himself, plundering his father's collection of armament.[8] The armor somehow interacted with the final stage of mutation and provided a moderator that contained and controlled the release of his body's energy.[9]

Jack of Hearts[]

Calling himself Jack of Hearts as a tribute to his father's passion for playing cards, he embarked on a mission of vengeance. Initially his quest for vengeance on the Corporation was blind and intolerant, leading him into conflict with such innocents as the Hulk and White Tiger, whom he believed responsible for his father's murder,[10] although they teamed up to take vengeance on the Corporation, receiving assistance from Iron Fist and Shang-Chi during the final battle.[11] Later he aided Iron Man in freeing Stark International from takeover by Mordecai Midas, and was taken under Iron Man's tutelage for a brief time.[12]

When his energy powers began to increase uncontrollably, he placed himself into S.H.I.E.L.D. custody. Chaffing in isolation, Jack eventually broke S.H.I.E.L.D. quarantine to meet a former classmate of his, Marcy Kane, who was also actually a Contraxian. She revealed to him his mother's extraterrestrial origin and convinced him to accompany her back to Contraxia to try to save their sun.[13] On Contraxia, a cult calling themselves the Survivalists captured Jack of Hearts to force him to do what he was intending to do anyway. He was flown in a starship to Contraxia's sun and there vaporized the craft before sending the energies of his body into the sun. In some as yet unknown manner, he apparently restored the vast quantities of hydrogen necessary to sustain the nuclear reactions of the sun, and added an undisclosed number of years to the sun's life. Then, still radiating great energy, he returned to Contraxia, his vast heat melting the polar icecaps, in order to say farewell to his girlfriend and to lecture the Contraxians about morality. He then flew off into outer space, realizing that he could no longer live among organic beings with his vast energies emanating out of control.[14]

Captured by the Stranger[]

Under unrevealed circumstances, Jack of Hearts was captured by the enigmatic alien, the Stranger, and placed on his planet for study. Jack of Hearts was inadvertently freed by the Avenger Quasar, who had traveled to the Stranger's world for his own purposes. Joining other refugees of Earth, Jack of Hearts returned to their native planet, only to be duped by another refugee, the Presence, into fighting Quasar. His armor was breached in the fight, and Jack appeared to have exploded in a burst of Zero energy.[15]

Actually, Jack was rescued and healed by the Moondragon, in her bid to gain an ally to prove herself as a worthy consort for Quasar. Jack proved overzealous as a mentally-influenced agent of Moondragon, who soon abandoned her designs on Quasar anyway, and Jack was released from her control.[16]

Jack sequestered himself in the abandoned Hart residence, but found his condition rapidly deteriorating, as his energies again threatened to go out of control. Returning to space, Jack sought out the alien Silver Surfer for help. The Surfer led Jack to an alien armor-wielder, who created a new and better energy-regulating armor for him.[citation needed]


After being severely injured while opposing the evil Tyrant, Jack was put under the care of the celibate Ganymede,[17] who nursed him back to health. Jack quickly developed feelings for her, and, while they were together on an idyllic planet, Ganymede almost broke her celibacy vow, but the two were then attacked by a remnant of Tyrant's army, and Ganymede realized her duty to avenge Tyrant's victims wasn't finished, going back on her decision and keeping her vow. As a heartbroken Jack prepared to leave, she grabbed his shoulder and told him that just because she wouldn't break her vow "yet", that didn't mean she wanted to be alone, and so they remained together a while longer.[18]

Jonathan Hart (Earth-616) and Ganymede (Alien) (Earth-616) from Cosmic Powers Vol 1 3 cover

With Ganymede

At one point, they were approached by Thanos and Terrax, who sought Ganymede for their own agenda. Without further explanation, Terrax attacked Ganymede while Thanos handled Jack. Ganymede successfully overpowered Terrax, but Thanos defeated Jack and then caught Ganymede off guard, knocking her out. They then took her unconscious, while Jack lay powerless on the floor, too weak to do anything about it.[19]

Worried about Ganymede, Jack enlisted the help of Genis-Vell and tracked Ganymede to the Tyrant's base. Jack was ready to fight for the release of Ganymede, but he stopped with the revelation that she had willingly agreed to help Thanos to stop Tyrant. Jack was quite shocked at first, but agreed to join them as well. In the end, however, Thanos betrayed the group to pursue his own goals, leading them to abandon him as he fought Tyrant.[20] Not long after, Ganymede cut ties with Jack to focus solely on Tyrant's demise.[21]


While journeying through space, Jack of Hearts happened upon agents of the cosmic beings known as the Infinites, an encounter that left him nearly dead. The incident also alerted members of the Avengers, including Moondragon. The Avengers rescued Jack and Moondragon helped restore his armor to his original design with several sophisticated upgrades. Jack and a team of Avengers confronted the Infinites directly, convincing the beings of the danger they posed to the universe.[22] Afterwards, Jack remained alongside the group to confront a galactic federation's decree that Earth should become a penal colony for the universe's known criminals, and he helped expose the alien Kree as masterminds of the plot. Returning to Earth, he helped the Avengers round up the remaining criminals and also helped the Avengers set up new security and analytical tactics to become a more effective team.[23]

Jack remained with the Avengers for several missions, including those against the time-traveling Kang when he nearly succeeded in conquering the Earth. During this time, the Avengers extended membership to Jack in gratitude for his efforts, and he readily accepted. The Avengers also developed a new strain of neutro-mist that allowed Jack to exist safely outside his armor for short periods of time.[24]

Avengers (Earth-616) from Avengers Vol 3 43 001

Welcomed into the team

The neutro-mist's effects didn't last, however -- eventually Jack's power levels became so hazardous, he needed to spend an increasing number of hours a day in isolation in the "Zero Room". The strain of isolation made Jack increasingly stand-offish and aggressive, causing him to clash with his teammates, particularly Ant-Man.[25]

When the Earth's Mightiest Heroes were recognized by the U.N. as a sovereign nation, Jack remained with the team, despite struggling with his motivations for being a hero.[26] One of their first missions after this historical event led them to South Dakota, where a mysterious red cloud started killing people in a matter of seconds upon contact. Despite some conflicts with the U.S. military, the whole team, with the exception of the immune Jack, donned protective suits and ventured into the red cloud to solve the mystery. There, they discovered a secret government lab and realized the cloud was an American bio-weapon. While investigating further, She-Hulk's protective suit was compromised and Jack tried to get her out of the cloud to save her life, but unintentionally absorbed her gamma radiation and made her revert to her human form, further complicating her situation.[27]

The accumulated stress made She-Hulk lose control of her powers and unleash her savage personality.[28] She injured several Avengers and went berserk in Bone, Idaho, virtually destroying the whole town. With her fear and rage at an all-time high, the assembled Avengers couldn't stop her. Only the Hulk himself was able to slow She-Hulk down until Jack of Hearts used his powers to balance her gamma levels and help her regain control over her savage side.[29]

With She-Hulk and Jack's ability to safely co-exist in question, the Avengers and Jack agreed that he would leave the team to focus on solving the issues with his powers. While attempting to patch up his relationship with Jack, Ant-Man was called away by a phone call, as his daughter had been kidnapped. Despite barely having 30 minutes left before his powers spun out of control, Jack followed Ant-Man, and stopped him from shooting his daughter's kidnapper in front of her. Finally finding his motivation for being a hero, but with not enough time to make it to the Zero Room, Jack snatched up the kidnapper and flew him into space. As his timer reached zero, Jack exploded, his body crumbling to dust in Earth's orbit.[4]

Jonathan Hart (Earth-616) from Avengers The Children's Crusade Vol 1 5 0001


Sometime later, Jack's body was reanimated by the Scarlet Witch when she attacked the Avengers due to a mental breakdown. Jack returned to the mansion and abruptly exploded, seemingly killing Scott Lang and damaging the Mansion grounds.[30] Lang would actually survive due to the intervention of the time-travelling Young Avengers, namely his daughter Cassie, who pulled him to the future seconds before Jack exploded.[31]


Jack was later seemingly brought back to life by Project P.E.G.A.S.U.S. using mysterious Z-Energy previously utilized to create a Zombified Squadron Supreme. At first, he was unaware of who or where he was and promptly fainted,[5] but Captain Jill Harper, one of Project Pegasus' security officers, appealed to his inner hero and made him remember who he was.[32] With a new purpose to fight for, he destroyed the zombie Squadron before sharing a kiss with Jill.[33]

Sometime later, Jack was captured by Mark and April Booth, two scientists who were trying to obtain Hulk-like powers. The couple had previously experimented with She-Hulk's blood, but the procedure had some unforeseen side effects, so they planned to use Jack's zero energy to absorb her gamma energy and remedy the situation.[34][35]

During a rare moment of clarity, Jack managed to break free and felt compelled to find She-Hulk,[34] but as he got to her apartment, he collapsed on the floor.[36] With no memories of anything since his sacrifice in Earth's orbit, Jack was surprised to learn he was now able to eat, drink, and sleep for the first time since his accident,[34] which meant he also had to use the bathroom and shower for the first time in a long time.[37]

While the two of them were trying to solve this mystery, they were attacked by Mark, who was able to go toe-to-toe with She-Hulk. Before long, however, the fight was interrupted by April, who dismissed the whole thing as an accident. She-Hulk wasn't convinced, but Jack believed them and they let them go.[38] As time passed, She-Hulk and Jack grew closer and became romantically involved.[39] One day, after She-Hulk missed dinner, Jack decided to go look for her and, with the help of a radiation detector, tracked her down to Mark and April's house. When he got there, April was about to absorb She-Hulk's gamma energy, but his distraction was enough for She-Hulk to break free. A fight ensued as Jack finally put the pieces together and realized who April and Mark were. Knowing only he could stop them, Jack then shattered the tank containing his zero energy and reabsorbed it, collapsing on the floor.[40]

Jonathan Hart (Earth-616) and Jennifer Walters (Earth-616) from Fantastic Four Vol 6 40 001

With She-Hulk, during the Reckoning War

April and Mark escaped, but She-Hulk remained by Jack's side as he remained unconscious.[40] When he regained his senses, he had his powers back and, in fear of absorbing She-Hulk's powers once more, decided to run away from her, breaking her heart. He stayed hidden for some time and, after making sure he wasn't leaking radiation or absorbing it without contact, finally paid She-Hulk a visit. She was emotional to see him again, and he confessed he was afraid to return to her, knowing they could never touch again, but She-Hulk asked him to let it be her decision.[41] They then began superheroing together and, when the Reckoning War that She-Hulk had feared for years ensued, the two joined the Fantastic Four to help put an end to it.[42][43]

His relationship with Jen once again took a step for the worse when the two ran into Jack's old flame, Ganymede, while on a romantic getaway. Having spent ages without seeing Ganymede, Jack was eager to reconnect with her, leaving She-Hulk feeling neglected.[44]

To complicate matters, Ganymede accepted a job with Drapurg, an alien whose invasion of New York had been thwarted by Jack and She-Hulk sometime before. When Drapurg ordered Ganymede to attack She-Hulk, she complied until Jack intervened and convinced her She-Hulk was one of the good guys. Ganymede then turned on Drapurg and apologized to She-Hulk before leaving with Jack. Heartbroken, She-Hulk prepared to go back home alone, but Jack returned and confessed his love for her. The two had a long heartfelt conversation, but, by the end, they seemed stronger than ever.[45]


Power Grid[48]
:Category:Power Grid/Fighting Skills/Some Training:Category:Power Grid/Energy Projection/Single Type: Long Range:Category:Power Grid/Durability/Superhuman:Category:Power Grid/Speed/Warp:Category:Power Grid/Strength/Superhuman (800 lbs-25 ton):Category:Power Grid/Intelligence/Gifted


Jack of Hearts possesses a number of superhuman physical and energy-manipulative capabilities as a byproduct of cellular mutation.

Zero Energy Blasts: Upon making contact with the experimental Zero Fluid, created by his father, Jack of Hearts' body underwent mutation at the cellular level allowing him to project powerful beams of concussive energy from his body. The energy itself is generated through unknown ways by the cells in his body and can be directed and controlled through conscious thought. This energy, referred to as Zero Energy, is generated constantly by his body and is emitted in negligible amounts whenever his cells have reached the maximum amount of energy they can store. He typically directs the energy consciously through his hands and is capable of creating a powerful shock wave of unknown limits. Whenever he discharges the energy consciously, the discharge is accompanied by a pink-colored light.[citation needed]

  • Flight: Jack of Hearts is able to direct the blasts of his Zero Energy downward for the purposes of generating sufficient thrust to allow him to fly. However, he must keep his arms pointed beneath him while in flight and is unable to use his energy as an offensive weapon unless an opponent happens to be directly in the path of the energy while in flight. The maximum speed he can attain while flying isn't known, but he has flew from Philadelphia to St. Louis in three minutes[46] and it is thought that he can use the Zero Energy to open hyperspace warps while in space allowing him to travel at speeds faster than light.
  • Superhuman Strength: Jack of Hearts' entire metabolic structure, bone, and muscle tissues have been transformed and augmented due to the mutagenic effects of the Zero Fluid. His strength has been known to fluctuate dramatically with his overall power levels. At his peak, he possesses sufficient superhuman strength to lift at least 25 tons. Jack has gone toe to toe with beings with much greater strength, though that could be due to a combination of his strength coupled with his energy powers and his body's great resistance to physical injury.[citation needed]
  • Superhuman Stamina: Jack of Hearts' augmented musculature generates less fatigue toxins during physical activity than the musculature of a normal human. At his peak, he can physically exert himself for roughly 24 hours before the build up of these fatigue toxins in his blood begins to tire him appreciably.[citation needed]
  • Superhuman Durability: The effects of the Zero Fluid have also augmented Jack of Hearts' bodily tissues, rendering them much more resistant to physical injury than those of a normal human. He has been known to withstand great impact forces, such as being struck by a superhumanly strong adversary, with little to no injury whereas a normal human would've been severely injured or killed outright. He has also demonstrated resistance to high caliber bullets, falls from great heights, and being struck by powerful energy blasts. Jack of Hearts also requires much less oxygen than a normal human and can survive unprotected within the vacuum of space for extended periods. While traveling in space has shown to have no detrimental effects on his body, he must enter an oxygen-rich atmosphere from time to time. His body is particularly augmented for the rigors of traveling at extreme velocities. Flying unprotected at high speeds, as Jack of Hearts does, would severely injure a normal human. When he has to breathe, Jack of Hearts can do so with complete ease even while traveling at speeds of hundreds or thousands of miles an hour whereas a normal human would suffocate.[citation needed]
  • Accelerated Healing Factor: In spite of his great resilience, it is possible to cause Jack of Hearts injury. If injured however, his augmented metabolism enables him to fully heal mild injuries more than twice as fast as an average healthy human. The full limits of this ability is uncertain as, for example, it isn't known of Jack of Hearts can merely heal normal injuries or if he can fully regenerate damaged or destroyed tissue.[citation needed]
Scanalyzer Enhancement: After being exposed to a Scanalyzer powered by a Symbiot Energy Sump device, Jack of Hearts' underwent another mutagenic alteration that allowed his encephalic patterns to be overlaid with the Scanalyzer's artificial intelligence. This enhanced his consciousness to a level where he can think at the speed of a computer, as well as retain and retrieve stored information with computer logic along with the human brain's naturally large storage base.[citation needed]


Jack is a good hand to hand combatant, having had some training in unarmed combat by S.H.I.E.L.D. However, Jack tends to rely on his energy blasts during combat situations.[citation needed]


While his body can potentially withstand the rigors of outer space indefinitely, Jack of Hearts still requires oxygen to survive, albeit much less than a normal human. Hence, if he finds himself in a vacuum environment for too long, it will prove fatal to him.[citation needed]



Jack of Hearts wears a suit of tough, boron-whisker-impregnated, steel alloy cloth, articulated body armor that covers all of his body except his face and hands. This suit of armor has somehow become absorbed by the mutagenic effects of the Zero Fluid vapors and incorporated into Jack of Hearts' body.[citation needed]


  • Jack's death occurred on May 5th, or at least that was the date when he was filed as inactive.[30]

See Also

Links and References


  1. 1.0 1.1 Official Handbook of the Marvel Universe A to Z #5
  2. Silver Surfer Rebirth #4
  3. Silver Surfer Rebirth #5
  4. 4.0 4.1 Avengers (Vol. 3) #76
  5. 5.0 5.1 Marvel Zombies Supreme #2
  6. Marvel Team-Up #134
  7. Deadly Hands of Kung Fu #22
  8. Deadly Hands of Kung Fu #23
  9. Deadly Hands of Kung Fu #24
  10. Deadly Hands of Kung Fu #2223
  11. Deadly Hands of Kung Fu #31
  12. Iron Man #103113
  13. Marvel Team-Up #134
  14. [[Jack of Hearts 1-4|[[Jack of Hearts #1|Jack of Hearts 1]]-4]]
  15. Quasar #1921
  16. Quasar #2729
  17. Silver Surfer (Vol. 3) #82
  18. Silver Surfer Annual #6
  19. Cosmic Powers #3
  20. Cosmic Powers #46
  21. Cosmic Powers Unlimited #3
  22. Avengers: Infinity #14
  23. Avengers (Vol. 3) #3538
  24. Avengers (Vol. 3) #3856
  25. Avengers (Vol. 3) #6162
  26. Avengers (Vol. 3) #61
  27. Avengers (Vol. 3) #6569
  28. Avengers (Vol. 3) #6768
  29. Avengers (Vol. 3) #7375
  30. 30.0 30.1 Avengers #500
  31. Avengers: The Children's Crusade #5
  32. Marvel Zombies Supreme #4
  33. Marvel Zombies Supreme #5
  34. 34.0 34.1 34.2 She-Hulk (Vol. 4) #2
  35. She-Hulk (Vol. 4) #8
  36. She-Hulk (Vol. 4) #1
  37. She-Hulk (Vol. 4) #3
  38. She-Hulk (Vol. 4) #5
  39. She-Hulk (Vol. 4) #6
  40. 40.0 40.1 She-Hulk (Vol. 4) #9
  41. She-Hulk (Vol. 4) #10
  42. Fantastic Four: Reckoning War Alpha #1
  43. Fantastic Four (Vol. 6) #40
  44. Sensational She-Hulk (Vol. 2) #67
  45. Sensational She-Hulk (Vol. 2) #78
  46. Avengers (Vol. 3) #56
  47. Official Handbook of the Marvel Universe A to Z #5
  48. Official Handbook of the Marvel Universe A to Z Vol 1 5