Here is the full list of all 23 Merlin Adventurer Store achievements.
Jackson reaches lv.100
Tanuki reaches lv.100
Kim reaches lv.100
Flamingo reaches lv.100
Reach the true ending
Reach NG+++
Martin reacheslv.100
Reach NG++
Meet all 24 characters
Reach NG+
Sell 1000 goods.
Earn 10,000,000 golds
Unlock all the dialogues of the Sister
Unlock all the dialogues of the Courier
Win the first place in the normal end
WuJie reaches lv.100
Unlock the 10th dungeon.
Get 800 prestige points
Earn 1,000,000 golds
Get 800 points style points
Unlock all blocks of your decoration area.
Unlock the 2nd dungeon.
Entered the game for the first time.