Twilit Vermin

Shadow Vermin, also known as Twilit Vermin, are twilight-corrupted Rats from The Legend of Zelda: Twilight Princess. Unlike most twilight monsters, Shadow Vermin bear virtually no resemblance to their normal counterparts, appearing as a black, tentacle-covered mass. They are the first enemies encountered as Wolf Link, appearing throughout the sewer under Hyrule Castle. Like normal Rats, they are quite weak but fast, and are also able to skim quickly across water. They also appear in caves, on Death Mountain, and in the Palace of Twilight.