Snorri

Snorri is an old, old ice giant. While he is still a warrior for the Sons of Hodir, he needs a bit of help these days to deliver havoc upon his enemies.

He appears at Fjorn's Anvil while the character is undertaking the quests

As a vehicle
Snorri is involved in the quest. During this quest, you mount him, and guide him to mounds of snow, which he packs into a snowball, and then have Snorri throw the snowball at a fire revenant, dispersing it.

Once a snowball has been picked up, you have 20 seconds in which to target a revenant and throw the snowball. One snowball, one revenant. Pfsssssss....