Stoor Worm

Monstrous: can block flying creatures and
can only be blocked by brave.
"An inhabitant of the sea, the stoor worm was a mythical serpent-like creature created by malevolent spirits. A gigantic beast with a ferocious appetite, it was able to demolish ships
and houses with its prehensile forked tongue it
used as a pair of tongs, and even to drag entire
hillsides and villages into the sea."