The Arctic Wyvern is frost blue, covered in scales and icy spikes.
The wyvern will either strafe the Master, attacking with it's hind-claws, or hover in the air and spit out two icy spheres which break into ice chunks when they impact the snow-covered tree. The strafing run can be dodged by moving out of the flight path, and the frost breath can dodged by running underneath the wyvern.
There's not much time or opportunity for melee strikes, and it's too dangerous to close to melee. Using Magic is the best and safest option, and a few castings of Magical Stardust will destroy the monster.