Jay was the son of Thomas Guthrie, referred to as both "Ty" and "Zeke," and Lucinda Guthrie. Jay's older siblings Sam and Paige were mutants as well, and both had been members of the X-Men. Another of their siblings, Jeb, developed the mutant ability to project electricity from his eyes. His mutant sister Melody was de-powered during M-Day. Jay had several other brothers and sisters, and his whole family was generally hated by his home town due to the fact that they all seemed to be developing mutant powers. When Sam and Paige left home to become X-Men, Jay took over the role of the father in the house, feeling that he had to protect his younger brothers and sisters.
Before Jay developed powers, he helped his brother Sam rescue the mutant musician Lila Cheney, the mutant Dazzler, and a third band member from a plane crash. Lila had been knocked out, rendering her unable to use her teleportation abilities. Dazzler had ran out of the sound needed to fuel her light based powers. Jay, risking his own safety, played some music, giving Dazzler sufficient power to help blast an escape route.
When Jay himself developed mutant powers, he hid them from his family. However, when performing in his band, playing guitar, he exposed his wings to the crowd as a 'stage gimmick'.
Jay fell in love with Julia Cabot, but due to a long feud between the Guthries and the Cabots a fight broke out. Jay was struck down by Julia's father, who had acquired and modified super-powered armor. Believing Jay to be dead, Julia dragged Jay's body to the river. She wrapped his arms around her, heading for the deepest part of the river. The two sank to the river's bottom and Julia subsequently drowned. Neither Jay nor Julia were aware of Jay's mutant regenerative powers, but when Jay sank to the bottom of the river, these powers manifested. Jay awoke at the bottom of the river with Julia in his arms. He swam to the surface with her and brought her to the riverbank. When he discovered she was dead, he tried (unsuccessfully due to his healing factor) to stab himself in the heart with a sharp piece of wood. Angel arrived on the scene, found Jay, and helped him carry Julia's body back to the Guthrie house.
After Julia's death, Jay attempted to kill himself a few more times, hoping his healing factor would fail. Eventually his mother sent him to the Xavier Institute against his will. Jay speculated this was just so she wouldn't feel guilty if he tried to hurt himself again. Originally placed with the Hellions squad, he traded places with Wither and joined the New Mutants. In New X-Men: Academy X, he's portrayed as a sullen, withered loner who keeps mostly to himself, but he always reminded his teammates how fortunate they were to be a "family" when they feud. His team talked to him about their problems, as he wasn't usually one to join the fights.
Decimation & Death
After M-Day, Icarus was one of the few of the New Mutants Squad team who kept their powers. However, someone cut off his wings and left him bleeding at the doorsteps of the mansion. His healing factor did not cure these injuries, as it was later revealed by Dr. McCoy that his healing powers came from his wings. Jay rebuffed efforts by his friend Elixir to heal his wings.
Jay was seemingly tricked by William Stryker, who told Jay if he gave his wings "back to God" his friends would be saved by Stryker. Jay called to inform him the children were leaving on a bus, which led to its bombing. Many of the de-powered students died in the blast. Further attacks led to the assassination of Wallflower, as she was the one in Nimrod's vision of the future that killed the Purifiers. As X-23 put it to Dust after he gave her a piece of paper containing the address of Stryker's church, he shouldn't be trusted because "he smells like death". Choosing to trust Jay, Sooraya seemingly proceeded to the church, only to be gunned down upon entering (though it was later revealed to be X-23 dressed in one of her niqab). After this, Stryker confessed he was responsible for the death of Julia Cabot, having given the other Cabots the armor, and he proceeded to shoot Jay. Icarus was then shown dying with Nimrod deciding whether or not to finish him off. Nimrod left Jay alone, calculating that he was already mortally wounded. After that, Icarus was found dead by Ms. Marvel and Iron Man in Stryker's church with his hand in a position of writing, he was able to write "NIMR" plus half of the "O" with his own blood before he died.
Later, a memorial service was held for Icarus, as well as all of the other students who had died. The memorial was attended by the X-Men and Icarus's family including Husk, Aero, Cannonball and their mother Lucinda.
Dawn of X
Years later, following the foundation of a mutant state on Krakoa by Charles and his allies, Jay was reborn on the island thanks to The Five, a group of mutants able to combined their powers into a processe of resurrection. He is shown living in the Akademos Habitat along with his siblings Sam, Paige and Melody. 
Powers and Abilities
Wings: Icarus could fly by means of his natural wings. Fully feathered like a bird's wings, Jay's wings' flexible skeletal structure enabled him to press them to the back of his torso and legs with only the slightest bulge visible under his clothing. It could be assumed that like Angel, Icarus could reach a height of 10,000 ft. with little effort. With severe strain he could reach the highest recorded altitude of a bird in flight, but he could only remain at that high for several minutes. He could fly nonstop under his own power for a maximum of approximately 12 hours.
- Enhanced Human Regeneration: He regenerated and healed hundreds of times faster than a normal human.  Thanks to this superhumanly regenerative "healing factor", he was able to completely heal from injuries which would prove fatal to most humans, even with superhuman abilities. However, Icarus revealed that a wound near his heart never fully healed, though this could just be metaphorical. His healing factor came from the natural regenerative enzymes secreted by his wings. It is currently unknown if his healing factor cured diseases or if he could heal through blood transfusion like Angel.
- Peak Human Strength: Jay had greater strength than what his size, age, and build would suggest. He was, like Angel, capable of lifting 500lbs at his peak.
- Superhuman Stamina: Jay's muscles produced far less fatigue toxins than an ordinary human's. This allowed him to operate at peak capacity for several hours before the build up of these toxins in his blood would begin to impair him. It is likely that he could fly for about 12 straight hours like angel before beginning to tire.
- Superhuman Durability: Jay's body, while far from invulnerable, was far more resistant to blunt force trauma than an ordinary human. This was mainly so that he was able to withstand large amounts of friction while in flight.
Aerial Adaptation: Icarus's entire anatomy was naturally adapted to flying. His bones were hollow, like a bird's, making him weigh far less than usual for a male of his build. His body was virtually devoid of fat and possessed greater proportionate muscle mass than an ordinary human did. His eyes were specially adapted to withstand high-speed winds which would hurt the average eye. He possessed a special membrane in his respiratory system enabling him to extract oxygen from the air at high velocities or altitudes. Icarus's physical adaptations gave him incredible protection against damage from falling.
Vocal Manipulation: He possessed a set of vocal cords that produced a sonic frequency beyond the range of human capability as well as creating multiple sounds or voices at once. The vocal ability allowed for more vocal control, such as hypnosis. He could also copy any sound he had heard or imagined.
Musical Talent: Icarus played the guitar and, regardless of his mutant ability, was an excellent singer as well.
His power to heal came from his wings; without them his healing factor didn't work.
- Jay was a deeply spiritual individual, though for reasons unknown, he kept this mostly to himself - sharing such with only a chosen few.
- One of the reasons Icarus's name was changed was because there was already a New Mutant named Joshua (Elixir) and the writers wanted to avoid confusing readers with two characters on the same team with the same name.
- Given his wings and healing powers, Jay is sometimes considered to be a Cheyarafim by fans.
- Jay had the beginnings of a relationship with Dust. As told by Nunzio DeFillippis and Christina Weir, had they continued their relationship, Jay would have converted to Islam.
- He was previously drawn with a tattoo on his arm, but later it was no longer present. Writers explained his healing power removed it.
- Icarus's relationship with Julia Cabot has often been compared to Romeo and Juliet. Even his lines with her are a modern version of the lines in Romeo and Juliet. The only difference is that Julia kills herself and Icarus comes back from being seemingly dead instead of the other way around.
- Icarus took his name from a character in greek myth named Icarus, who made wings out of wax and fell to his death after flying too close to the sun. Icarus didn't choose his name because of the greek Icarus's wings, he chose it as a metaphor for, as he says, "how far I've fallen".
- Exactly half of the Guthrie kids are mutants (Cannonball, Husk, Icarus, Aero, and Jeb) and exactly half of the Guthrie family's mutants were depowered (Aero and Jeb were depowered after M-Day and Icarus kept his powers, but lost them when his wings were cut off, meaning he was one of the 198 and was also depowered).
- 53 appearance(s) of Joshua Guthrie (Earth-616)
- 4 minor appearance(s) of Joshua Guthrie (Earth-616)
- 12 mention(s) of Joshua Guthrie (Earth-616)
- 45 image(s) of Joshua Guthrie (Earth-616)
- 1 quotation(s) by or about Joshua Guthrie (Earth-616)