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