Ambush Bug is a fictional comic book character who has appeared in several DC Comics. His first appearance was in DC Comics Presents #52 (1982).
His name is supposedly Irvin Shwab, but it must be noted that he suffers from mental problems that prevent him from truly understanding reality around him, so even his true identity might be no more than a delusion on his part. Nothing is known about his origins.
Created by writer Keith Giffen as an intentionally silly character, Ambush Bug first appeared in several Superman-related comic books in the early 1980s. At first, Ambush Bug was a villain, named after a type of insect, and dressed in a green, skintight suit (with two orange antennae) that covered his whole body. (Without his costume, Irving was seen to be a skinny, hairless man.) Inside his hollow antennae, he carried miniature robot bugs that possessed the ability to teleport him around. After attacking Superman and other heroes (and being little more than an annoyance to them) Ambush Bug decided instead to be a superhero as well. He also fancied himself Superman's friend, which only annoyed the hero even more. After a supposed accident with his inventions, the costume became permanently affixed to his body, and he gained the power to teleport by himself. (Again, it's unknown if this is true or just another delusion of his.)
Ambush Bug became popular enough to be featured in three comic book miniseries, written and drawn by Keith Giffen. However, these became increasingly surreal, to the point that they cannot be seriously considered part of the DC Universe. (It may be that the events of these series happened only within his imagination.) The series also contains many comic book-enthusiast and DC in-jokes and satire; series editor Julius Schwartz is also a character in the book.
During one of these series, he picked up a doll and, thinking it was alive, 'adopted' it as a partner called "Cheeks, The Toy Wonder", complete with its own costume.
Ambush Bug is largely considered an absurd character and is rarely used by other writers, though he still exists in the DC Universe and occasionally still appears in some DC Comics.