In Joking the Chicken, we see Iggy failing miserably to become a stand-up comedian. His style of humor was exceedingly P.C. and overly clean, and that's why nobody found them particularly funny.
Morris Needleman (King Chicken in disguise) had him drink a special "likeability formula" to get people to laugh at his awful jokes. He became an immediate celebrity, packing stadiums with audiences.
He did not know of King Chicken's true plan to isolate Duckman, and did not like that he was made to drink the formula in order to manipulate people.
After Duckman reveals to his audience what's happening behind the scenes, Iggy loses his fan base in an instant. But he wasn't too discouraged, and decided to move on to his lesbian jokes.
In Color of Naught, he also appeared in the "Beautex" infomercial, which was ironically another one of King Chicken's plans.
He mentions that he moved past his career as a stand-up comic, and is now hired as a guy who finds virgins for Fox executives.
We see that he's used the Beautex line of products, and his life has turned around because of it. He became confident, secure, and he's getting more tail than he can handle.
In The Mallardian Candidate, Iggy approached Duckman and Cornfed with a case, which was later revealed to be bait for Duckman.
Iggy was the evil genius at the World Domination League (WDL), the global conspiracy behind the greatest conspiracies of the planet, and they conducted a brainwash on Duckman.
In an attempt to murder the one detective that could stop them, Duckman was brainwashed by them into hunting down Cornfed.
However, in a further twist, this wasn't Iggy at all, but a robotic surrogate as an ironic plot twist.
- Roulette made a joke once about he looks like glasses on a turd.
- In Color of Naught, Iggy mentions that once somebody called him a jackanape. He didn't know what that means, but it's defined as "an impertinent person" or "a tame monkey".
- Under technicality, Iggy wasn't in The Mallardian Candidate at all, as that was simply a robot look-alike.