Frost Serpents

A relation of sea serpents, frost serpents actually dwell in the cold waters of the northern Serpent Isle.

Description
Instead of breathing normal fire like their green cousins, their breath either freezes their enemies or uses the blue cold-fire. Other than that, however, they share all other traits with regular sea serpents and can also be overcome in the same way.

Frost serpents are found in the cold waters of the northern ice regions.