Here is the full list of all 20 Flame Keeper achievements.
Kill 100 mobs having less then 25% health points
Kill 50 mobs with a glory kill
Kill each of the 3 species of monsters with your punch
Kill 100 mobs
Kill 100 enemies with your punch
Complete 1 stage without hitting any monster
Use dash to take off energy from 100 trees
Run 10000 units
Use Dash ability 100 times
Collect 500 energy balls
Regenerate 1000 health with energy balls
Finish 2 levels having at least 60% health
Eat 30 mushrooms
Fill 3 fireplaces having at least 70% health
Complete 2 missions in survival mode without losing energy
Find 2 negative effects
Fall 10 times from an island
Take 1000 damage from monsters
Die 1 times from wind
Fill 30 fireplaces