Grishnar cat

The grishnar cat was an animal with a fearsome appearance, but which in reality was quite harmless (at least when it was old and toothless).

Prior to attacking Deep Space 9 in 2372, Chancellor Gowron likened Captain Benjamin Sisko's claims of his station's upgraded defenses to a "toothless old grishnar cat", attempting to frighten the Klingons with his roar. 

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Grishnar-Katze