Here is the full list of all 56 Grim Clicker achievements.
Open 1 chest
Kill 20 fireflies
Click 5000 times
Get level 5
Reach Zone 5
Perform 1 ritual
Click 500 times
Kill 1 champion
Perform 10 rituals
Perform 20 rituals
Perform 50 rituals
Collect 50 Candles
Collect 100 Candles
Collect 250 candles
Collect 500 candles
Open 10 chests
Open 20 chests
Open 3 boss chests
Open 30 chests
Open shard chest
Upgrade any weapon
Upgrade any item
Dissasemble any item
Remove one lock
Remove three locks
Upgrade weapon to quality 5
Upgrade weapon to quality 10
Upgrade weapon to quality 15
Find people on the shard
Complete 10 quests
Complete 50 quests
Complete 100 quests
Get level 10
Get level 20
Get 5 strenght
Get 10 strenght
Get 15 strenght
Get 20 strenght
Get 5 dixterity
Get 10 dixterity
Get 15 dexterity
Get 20 dexterity
Get 5 wisdom
Get 10 wisdom
Get 15 wisdom
Get 20 wisdom
Kill 5 bosses
Kill 10 bosses
Kill 20 bosses
Reach Zone 10
Reach Zone 50
Kill 25 champions
Kill 500 champions
Kill 1000 fireflies
Kill 10000 fireflies
Click 50000 times