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