Shrewhale
These leviathans are able to burrow through the terra firma as easily as their oceanic counterparts can swim. They follow fault lines and sing alongside the earthquakes when they come. Their songs are too low frequency for most humanoids to hear in any meaningful way. But with the right instruments some Ecologists think that it might be possible to understand them and unlock the poetry of their calls.
Each has a face with a star of finger like protrusions, ideally suited to the underground. Not unlike some star moles. But behind their behemoth body, somehow molding their earth around themselves as they travel.