WARNING: The following contains spoilers for Iron Man #6 by Christopher Cantwell, CAFU, Frank D'Armata & VC's Joe Caramagna, on sale now.
While most Marvel mutants debut somewhere in the X-Men's world, Halcyon, one of Marvel's newest mutants, debuted by encountering Tony Stark in Iron Man. However, the young man's powers left a lot to be desired.
Halcyon is a mutant who has the mutant powers to keep his heart rate below 70 bpm at all times. This means that Halcyon will never flinch regardless of the danger around him. This might make him a master in street racing, but he provides little offense in a fight. The fact that Iron Man brought him into the battle against Korvac seemed a little confusing.
After Iron Man broke his neck and was one step away from death in Iron Man #6, Halcyon proved that he might be one of Tony Stark's most valuable teammates because he brings something much more important than being another superhero who can punch villains.
If anyone took Iron Man's helmet off, Tony Stark would've died without medical intervention and surgery. Neck surgery like this would also take Iron Man out of action for an extended period of time. With Korvac trying to power up and do unspeakable deeds, Iron Man refused to sit this battle out, which meant that he had to get back into the fight, even if he had a broken neck.
Thanks to his mutant powers, Halcyon has a low heartbeat allows him to do anything he wants with nerves of steel. As a street racer, he is also someone who has to keep his car in tip-top shape. This means he has mechanical skills, and that is something that Tony Stark puts a premium on. Between these two tings, Halcyon was able to help get Iron Man back on his feet thanks to his mechanical skills and iron-clad nerves.
By fusing the armor's cervical column rings, Halcyon kept Tony Stark from suffocating. He then torqued the interior chassis structure of Iron Man's neck to 113 foot-pounds, which further stabilized the fracture. Tony only has 50 degrees of head rotation, but between what Halcyon did and the painkiller cocktail Misty Knight gave him, Iron Man is now back in the fight.
When Halcyon first showed up, it didn't seem like he was going to be much help. He was a nice friend for Tony when it came to street racing and keeping him ready for anything. He was also a good person to have on the ground since he knew many people on the streets that Tony had no way of contacting. But there is so much more to the mutant than this.
Most importantly, he is a mechanic with iron-clad nerves. He can do what Tony needs on the fly, and he quickly became one of the most valuable allies that Iron Man has since his technology is a big part of what makes Iron Man one of Marvel's greatest heroes.