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