Tongue of Thunder!

Mount P’toovius — forbidding, aloof, terrifying. Towering over the windswept savanna, its snow-capped peak conceals a deadly secret: an active volcano capable of limitless, unpredictable destruction.

the underside of a cat's chin. The cat's white facial fur looks like the snowy peak of a mountain.
Mmmrrroooowwww…

Its eruption comes with little warning, merely a guttural growling punctuated by hisses. Then, in a fearsome plume reaching to the heavens, it explodes with an earth-shaking p’tooee!

the underside of a cat's chin. The cat's white facial fur looks like the snowy peak of a mountain. The cat's tongue sticks out like a plume from a volcano.
P’TOOOOOOEEEEEEEEEE!!!

Found by Andrew Y. on Ecchs.

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