My personal favorite is the Whorl Shark, which looks like something you’d see under water in World of Warcraft; the kind of thing you need to kill 20 times before you can turn in the quest.

Whorl Sharks were similar to their modern cousins despite jetting along almost 300 million years ago. While modern sharks have rows of serrated teeth ready to replace any that fall out, the whorl shark has an interesting lower jaw that looked like a circular saw, where newer teeth would push older teeth further along the line. There’s some debate about the placement of the tooth structure, but regardless of its location in the mouth or deeper in the throat, it had a startlingly unique appearance.

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