This discussion in the Mortal Online forums, about the next continent and what might be on it or in it, leads me to suggest: There could be 'sandworms' in Sarducaa and some other kind or colour of worm in Herabalter, along the lines of this
(as imagined by artist Pieter Dirkx)Mongolian Death Worm.
Also known as the Allghoikhorkhoi, this cryptid (its existence disputed and unconfirmed In Real Life) is described as a bright red worm with a wide body that is 2 to 5 feet (0.6 to 1.5 m) long. It's allegedly got corrosive poison spit, an electrical range attack, and a nasty habit of lurking underground.
In fact, this fable is probably the inspiration for Tolkien's references to "wild Were-Worms in the Last Desert". Whether real but rare or utterly fantastic, it's perfect for adoption into Mortal Online.