Toxic waste

Toxic Waste (also called Acid) is an uncommon obstacle in the Donkey Kong franchise.

The Toxic Waste makes its first appearance in the level "Toxic Tower" of the game, Donkey Kong Country 2: Diddy's Kong Quest. In this level, Diddy and Dixie Kong must climb a tower slowly filling with toxic waste, all the while being transformed into a multitude of Animal Friends.

"Toxic Tower" is later revisited in Donkey Kong Country 2's semi-sequel, Donkey Kong Land 2.

In Donkey Kong 64, some pools of toxic waste can be found in the area Creepy Castle.

One of Funky Kong's minigames in the Game Boy Advance remake of Donkey Kong Country 2 has the Kongs swerving around in their Gyrocopter collecting pieces of a golden statue of Donkey Kong all the while dodging lowering and heightening pools of toxic waste.