Chomper (called "The One That Got Away" by Ash) is a monstrous deadite that serves as the fourth boss battle on Evil Dead Regeneration. It protects the portal at the docks.
After 'passing through' Peepers for the third time, Ash and Sam come to a warehouse where the portal can be seen. However, the ground shaking ever quicker to the sound of footsteps draws their eyes as a monstrous amphibian-like beast bursts from the warehouse, roaring at the pair.
Avoiding Chomper's charge attacks and his tail spins, Ash focused his attacks on Chomper's spinner as the deadite impaled it in the ground. As Chomper roared in pain, Ash fired a shot from his Firelance down Chomper's throat. After repeating the process, Chomper is finally killed.
As Sam goes to close the portal (tripping over Chomper's tail in the process), Ash absorbs the evil spirit from within the monster before Professor Knowby's ghost appears to warn Ash that Dr. Reinhard has nearly put together his plan to allow the dead to take over the Earth Plane - which involves using Sally Bowline as a sacrifice.