How to Obtain
Mjoln-Ice can be found in Shiverchill Mountains. It is in the frozen chest in the Treasure Room. To obtain it, you have to get the last Power Crystal - obtained by battling a Wizard after completing the area - and light up the final furnace. Once you do, then the chest will be thawed. The wizard is in the spawn area. You should see an opening with light in the bottom left hand corner. You can actually go into the border lands from there and the wizard is there.
Mjoln-Ice adds 30 damage to your spells, making it tougher than most wands, in this case, the only hammer around.
It is a mystic hammer wielded by the great Frost Beard, some say the hammer grants the wielded the power of a Norse god.
- Mjoln-Ice is a reference to Mjolnir, Thor's hammer from Norse mythology (and the the movie).