Mab is a fae queen, a rival to Titania and Oberon. Styling herself the Queen of Air and Darkness, she presides over the faerie courts of Russia. Mab is known to have had a falling out with Odin and she has sworn to eat his heart should her ever return to her domain.

In combat, Mab makes use of Gungnir, a magickal spear that Odin left buried in her shoulder when he fled her realm. As a faerie, Mab is immune to magick, making her one of the few beings that Odin, the greatest living wizards, fears.