Here is the full list of all 20 Idol Hands achievements.
Collect 10,000 units of wood
Game completed by winning the final level
Destroy 10 buildings with volcanoes
Create 5 volcanoes in a single level
Throw 5 meteors in a single level
Complete level 5 onwards with only 6 farmers
Kill 200 enemy furlings
Complete all tutorials
Complete a level without losing one of your furlings
Trigger 10 earthquakes in a single level
Make it rain 20 times in a single level
Your priests have converted 20 enemy soldiers
Complete level 5 onwards with only 5 woodcutters
Throw 20 lightning bolts in a single level
Your priest converts his first enemy furling
Create your first army of 10 soldiers
Create your first priest
Expose your first iron ore
Finish "In the Beginning...", the first tutorial level
Play the game for the first time