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