Here is the full list of all 60 Legend of Grimrock 2 achievements.
Learn 15 spells
Reach level 10 with a farmer
Summon the Viper Roots in under 6 minutes
Cast 500 spells
Cast 250 Spells
Cast 25 spells
Complete the game with hard difficulty setting
Complete the game with old school mode
Complete the game with Ironman and Single-use Crystals modes turned on
Enter the Nexus
Visit all levels
Defeat the Lindworm
Find all secrets
Enter the Shrine of Balance
Enter the Castle
Collect and wear full set of Crystal armor (6 pieces)
Collect and wear full set of Meteor armor (6 pieces)
Collect and wear archmage's uniform (4 pieces)
Assemble the Meteor Hammer
Polymorph 10 times
Kill a monster by teleporting on it
Enter the Crystal Mines
Mix a total of 50 potions
Mix a total of 10 potions
Collect and wear rogue's wardrobe (5 pieces)
Dig up all treasure chests
Collect four elemental essences
Find 8 skulls
Defeat the Ratling Boss
Catch 25 fish
Open the door to the Archives
Find 50 secrets
Find the Relic
Defeat a Magma Golem
Find the pie
Travel 10000 tiles
Enter the Pyramid of Umas
Defeat the Wormbound brothers
Perform 100 power attacks
Kill 250 monsters
Defeat a monster with a backstab attack
Find Bane
Max out three skills
Open the gate to the Cemetery
Open 5 gold locks
Find 25 secrets
Perform 500 missile or throwing weapon attacks
Dive 250 tiles
Defeat Herder's Den
Kill a monster with a single blow
Visit 10 levels
Defeat the Summon Stones
Collect an elemental essence
Find 10 secrets
Max out a skill
Perform 500 melee weapon attacks
Dig up three treasure chests
Kill a monster by throwing pants at it
Defeat the Viper Roots
Deal a killing blow with unarmed attack