Here is the full list of all 26 Tribes of Midgard achievements.
Play a game with a Pet equipped
Craft a Rare Item in any Mode
Craft an Uncommon Item in any Mode
Reach Season Level 2
Craft a Common Item in any Mode
Spend 10,000 Souls in Miðgarð
Spend 100,000 Souls in Miðgarð
Spend 1,000,000 Souls in Miðgarð
Successfully revive a villager
Successfully revive an ally player
Reach Season Level 5
Reach Season Level 10
Complete a Saga Quest in Saga Mode
Reach Season Level 25
Reach Last Season Level
Complete the Tutorial
Reach Day 100 in Survival Mode
Have 100 Constructions in any Mode
Deliver the final blow to defeat an Ice Jötunn in any Mode
Deliver the final blow to defeat a Fire Jötunn in any Mode
Deliver the final blow to defeat a Thunder Jötunn in any Mode
Deliver the final blow to defeat a Dark Jötunn in any Mode
Deliver the final blow to defeat a Saga Boss in Saga Mode
Craft an Epic Item in any Mode
Craft a Legendary Item in any Mode
Hold 10,000 Souls or more in Saga Mode