Neptunian Slug

Neptunian Slugs are a species of slug native to the planet Neptune. There are two types of slugs, identified by their colour: the more commonly seen (and eaten) yellow, and the diarrhoea-inducing purple. One, if not the only, defensive manoeuvre they are capable of is to inflate themselves to over ten times their normal size, making them much harder to kill. Little else is known about the creatures; but, like Earthican slugs, salt causes them to deflate.

Trivia

 * Neptunian Slugs can also be kept as pets.