Here is the full list of all 31 Idle Clans achievements.
Receive a boss key
Equip diamond jewellery
Grow some watermelons
Eat a burger in battle
Achieved upon reaching your first million
Steal from the royal clan
Purchase your first property. It's nothing to brag to your parents about, but it's a start.
Enchant an item
Prepare a special dish
Defeat a dragon
Refine an item
Create silver jewellery
Send an item to your clan's vault
Join a clan
Create a clan
List an item for sale
Purchase an upgrade
Perform a leaderboard search
Plunder a small, helpless village
Your first level up
Join a minigame
Complete the tutorial
Reach a billion gold
Reach level 100 in a skill
Reach max level in a skill
Defeat a boss
The true test for any respectable chef... Make a pizza.
Create a godlike item
Battle a monster with an Outstanding weapon
Smith a piece of Astronomical armour
Purchase the most glamorous property available