Here is the full list of all 32 Idle Hero achievements.
Kill 1 enemy
Kill 10 enemies
Kill 100 enemies
Kill 1000 enemies
Kill 10000 enemies
Complete 1 level
Complete 10 levels
Complete 100 levels
Complete 1000 levels
Complete the game once
Complete the game 5 times
Complete the game 10 times
Buy 1 helper
Buy 10 helpers
Buy 50 helpers
Buy all helpers
Earn 10 gold
Earn 1K gold
Earn 100K gold
Earn 10M gold
Earn 1B gold
Buy 1 upgrade
Buy 10 upgrades
Buy 100 upgrades
Buy 1000 upgrades
Play for 1 hour
Play for 10 hours
Play for 100 hours
Defeat one boss
Defeat 10 bosses
Defeat 100 bosses
Defeat 1000 bosses