The Mandarin is a very prominent villain. He has ten rings with different powers which pose a great threat to Iron Man. Another one is Obadiah Stane, who was Iron Man's business rival and later became the Iron Monger. He was a formidable foe in the early storylines.
Baron Zemo is a major villain. He often schemes and creates chaos that forces Captain America and Iron Man to deal with his evil plans.
Aldrich Killian is another villain. He creates the Extremis virus and uses it for his own malicious purposes. He tries to get revenge on Tony Stark and cause chaos with his new - found power.
There's also Justin Hammer. He's a rival to Tony Stark in the business world. He's jealous of Stark's success and teams up with other villains to try and bring him down. He's not as physically powerful as the others but is quite devious in his plots against Iron Man.
Obadiah Stane is quite memorable. He was once close to Tony Stark but turns on him. His own greed and desire for power lead him to create his own version of the Iron Man suit and try to take over Stark Industries. His betrayal makes him a significant villain.
Mandarin is still a prominent villain in modern Iron Man stories. He has a long - standing feud with Iron Man and his devious plans often put Iron Man's world in jeopardy.
There's also the Crimson Dynamo. These are different individuals who take on the mantle of the Crimson Dynamo over time. They are usually Soviet or Russian - affiliated villains who have their own high - tech armored suits. Their battles with Iron Man often involve political undertones as well as just pure superhero - villain combat.
One of the main villains is Davos. He has a long - standing rivalry with Iron Fist. Davos believes he should be the one to inherit the power of the Iron Fist.
The main villains include Obadiah Stane, who is like a snake in the grass. He's been there with Tony from the start but then reveals his true evil nature. Mandarin is another big one. His power and his inscrutable motives make him a formidable adversary. There's also Whiplash. He has his own high - tech weapons and a vendetta against Stark. All these villains play important roles in making the Iron Man comic book story full of action and drama.
Most likely, Iron Man (Tony Stark) is the main character. There might also be Pepper Potts, who often plays an important role in Iron Man's life. And there could be some new characters created specifically for this 2020 Graphic Novel that interact with Iron Man in significant ways.
The Akatsuki could still be major villains, but with a twist. They could be interested in Naruto's connection to Iron Man and his technology. Maybe they want to use it to enhance their own powers or to create a new type of bijuu using Stark's technology. Another option could be a new villain from the Iron Man universe, like Justin Hammer, who finds his way into the Naruto world and decides to use the chaos there to his advantage by creating his own criminal empire using ninja and technology combined.