Pengator

The Pengator is a duck-billed mammal, appearing as a hybrid of alligator and penguin, found in the cold regions of Hyrule, in the Dark World in A Link to the Past. Usually residing in the freezing catacombs of the Ice Palace, they will hinder their prey by keeping their domain on sheets of ice, which will cause difficulty in the victim's walking. They would then lunge at their quarry with razor sharp alligator-like teeth from their penguin-like bill at very high speeds, sliding across the ice on their stomachs.

Link was able to dodge the attacks of the Pengators and then strike them with his sword several times, killing the beasts. This however is probably the least efficient way to dispose of them; instead, wait for them to line up and and come at you then use the Hookshot to kill them. The Fire Rod is also effective. Although Pengators do have wings, they cannot use them to fly, as the penguin is a flightless bird.