Here is the full list of all 13 Viking Rage achievements.
Kill 100 Enemies!
Fire an Axe with a Bow!
You completed the Tutorial!
Teleport 500 Times!
Loose a Level without Killing Enemies!
Kill 250 Enemies!
Kill 500 Enemies!
Kill 100 Enemies while in Rage
Kill the Mountainboss only using Axes
Survive a Level with less than 5% Health left
Kill 50 Enemies through Explosive Barrels or other Traps
Kill 100 Enemies with the Bow
Kill 250 Enemies with the Bow