Doofengung is the main antagonist in the Phineas and Ferb episode "Tri-Stone Area". He is the Neanderthal counterpart/possible ancestor of Heinz Doofenshmirtz. However, this version appears to be even more incompetent and childish than Doofenshmirtz, as he can barely speak like a caveman, and can only grunt his sentences, lacks the inventing skills like most of the other Doofenshmirtz counterparts, can get easily entertained by a drop of water, does not have a Norm counterpart, and gets defeated very easily, even without the need of his nemesis Bunka da Bunkaquan (the Neanderthal version of Perry the Platypus).
Just like his original counterpart, he was voiced by Dan Povenmire.
According to Doofengung, when he was a fish that was capable of walking on land and breathing air, he decided to go back into the water. Because of which, Doofengung was always one step behind to his younger bother; Ro-juh Doofengung, who seems to be more evolved, has a nice piece of land, and generally seem to have everything, while Doofengung is always stuck with the short end. In a fit of jealousy, Doofengung decided that he wanted Ro-juh's land. He does this by creating the Stick-Inator (which is just a sharp stick tied to another stick). He explains to a "captured" Bunka da Bunkaquan that if he jabs his Stick-inator onto a herd of Mammoths, they go on a rampage, which would cause Ro-juh and the other residents to run away from the stampede, causing them to leave the land. With no one to claim the land, Doofengung would claim the land for himself.
Minutes later, Doofengung processed with his plan. However, as he jabbed his Stick-inator on one of the mammoths, instead of going on a rampage as he was hoping, the mammoth looked at Doofengung with an anger gaze. Doofengung attempted to run away from the herd of mammoths, which resulted in the mammoths chasing after Doofengung. This result in Phinabunk and Gerb's cart and Doofengung's cave to be destroyed. Angry by this turn of events, Doofengung angrily curses Bunka da Bunkaquan for the failure of his plan, despite the fact that the prehistoric platypus actually had nothing to do with Doofengung's defeat at all.