Anti-Ducky is one of (many) sworn enemies of the (increasingly) tyrannical Ducky. His most notable features are his cold, souless eyes and his mohawk.
Anti-Ducky appeared on the scene during the climax of the First Ducky War, where he challenged Ducky to a duel. He was killed moments later when he could not withstand Ducky's Kill Quack. However, Bob Saget revived him because his death was funny. So began a long history of Anti-Ducky challenging Ducky only to be killed mere seconds later and revived shortly after that. This has fooled many to believe he's one of the Undefeatables, but he's not cause he gets killed so often.
2nd Ducky War
He fought in it, but he didn't last very long as he was killed by Gaston ...then Ducky ...then Dark Ducky ...then Ducky again...and then by Somebody else. FINALLY fed up with constantly dying and being revived, Anti-Ducky challenged Bob Saget to a duel...and was killed swiftly afterwards only to be revived and killed again. Of course, by now the concept had gotten boring and overused so Bob Saget kill him one last time and didn't revive him. Thus, Anti-Ducky was dead...
...or so everyone thought until he was revived by Quan Chi in order to kill Ducky. Hasn't worked so far, but he might get lucky one day. And we'll finally be free of- *dies*