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