D
- Doctor Doom - Has a similar relationship with/vendetta against Iron Man/Tony Stark as he does with Reed Richards, who is one of Tony's best friends. Is considered by many to be Iron Man's greatest enemy (and is a much greater threat to the Marvel Universe overall than The Mandarin.)
- Dreadknight - A disfigured scientist in knight armor with a vendetta against Iron Man and Doctor Doom.
Read more about this topic: List Of Iron Man Enemies