Here is the full list of all 18 Queen's Quest 3: The End of Dawn achievements. It takes around 4-5 hours to unlock all of the achievements on Windows.
Defeat the Dragon Lord.
Destroy the machine powering the crystal.
Complete the ritual.
Complete a Hidden Object Scene in less than one minute.
Find 30 Collectables.
Return the crystals to the witch.
Complete three Hidden Object Scenes in less than 10 minutes.
Find the Dragon Crystals.
Open the library.
Complete five Mini-games without skipping them.
Complete a Mini-game in less than one minute.
Complete a Hidden Object Scene without using a hint.
Find 3 hidden objects in three seconds.
Find one Collectable.
Finish every the Mini-games without skipping any of them.
Find every Collectable.
Finish every Hidden Object Scenes without using a hint.
Complete a Hidden Object Scenes without mistake.