The two serpents were not so little. They could not house their bodies the same way that Onyx did in his shadow. However, they were not the small palm sized serpents that Walker could recall. They could easily wrap around his waist three or four times now.
It also showed how one of them could use their dark magic affinity to manipulate shadows and push themselves to move through the terrain much faster for a short while by using everything they had. Or, in this case, moves through the cracks in the rocks to discover something like these ruins.
Part of Walker wondered if their classes would influence their growth. If they remained thinner to be able to move in to the ruins that they discovered or just to slither through smaller caves it would make more sense. Onyx had to grow larger to be able to follow his bloodline but also to combat monsters with the party. Not that he had had a class growing the way that he did.
