|This needs a stretch.|
Needed: Gold Key adaptation.
The Ape Man was the disguise of Carl the stuntman.
He was an ape with dark blue fur, and was rather tall. He had sharp teeth, a big snout, and red pupils with yellow sclera.
He was rather aggressive, trying to knock Candy Mint off a bridge.
Powers and abilities
The Ape Man appears to be strong, although he has rarely actually showcased extraordinary strength; instead he mostly uses his smarts to outwit and scare the gang.
According to the legend, the Ape Man burnt down the old mansion.
Scooby-Doo, Where Are You!
The filming of a scene in The Ape Man of Forbidden Mountain has gone awry due to the Ape Man acting more hostile than usual, being clear it's not the stuntman Carl in the costume, and instead of jumping on the bridge as scripted to knock Candy off, he shook the bridge. But Scooby-Doo, showing a rare case of courage, saves Candy and manages to knock the Ape Man away, but only temporarily. Among finding Carl the Stuntman locked in a chest in his room, he claims that it was the real Ape Man that locked him in, and claims he'll be quitting the movie, along with Candy Mint, if the case isn't solved.
The Ape Man overhears the Scooby gang's initial plan to catch him, and sets out to stop them. A clue he accidentally leaves behind is a half-eaten hamburger that he had been eating. One attempt at scaring Mystery Inc. away is sending a still stuffed Ape Man dummy on a wheeled platform at the gang, which Shaggy demolishes in his panic attack. Then, in a library set, he dons a rubber Scooby-Doo mask among seeing the real Scooby checking for clues on the shelves, coming to an opening and impersonating his reflection at a phony "mirror." Once revealed, he chases them, but Scooby manages to ward him off with his growling.
The gang comes up with another plan to capture the Ape Man, and among hearing this, he spies on the bait Scooby and Shaggy, initially pretending to be a stuffed trophy head. Then he sneaks up behind Shaggy when he and Scooby attempt to play pool, and winds up chasing the two, but the plan fails when Scooby accidentally fogs up Velma's glasses and she pulls a wrong switch, instead getting Shaggy caught in their trap. Then when Shaggy and Scooby are playing around with costume parts in a wardrobe trailer, Shaggy sees the Ape Man with his mask off, and snaps a picture with an instant camera. With his head back on, the Ape Man attempts to catch the gang again, but the chase through a set leads the gang to send the Ape Man sliding down a ramp and crashing into some furniture, where he is caught. Shaggy then shows the picture, revealing the Ape Man was indeed Carl the whole time, angry for not having gotten the lead role in the film and set out to sabotage it. 
Gold Key Comics adaptation
Insert details here. (Never Ape an Ape Man)