Here is the full list of all 15 Barbarian Brawl achievements.
Do damage to enemies
Take damage from enemies
Kill enemies with axe
Block enemy attacks
Kill enemies with club
Die more
Brynhildr kills
Kill enemies with halberd
Make some killing sprees
Kill enemies with knife
Mr. Rotten kills
Kill enemies with scythe
Stun enemies
Get survivor mark
Kill enemies with sword