Here is the full list of all 52 Ys: Memories of Celceta achievements. It takes around 50-60 hours to unlock all of the achievements on Windows.
Acquired all achievements.
Mastered every skill.
Played extensively as Calilica.
Acquired at least one of every item.
Filled out all material details in journal.
Proved your skill as a merchant.
Amassed one million gold.
Purchased every piece of info from Mouse.
Conquered Boss Rush.
Conquered Boss Rush without a single retry.
Defeated a boss in Time Attack without taking damage.
Defeated a boss in Time Attack in thirty seconds or less.
Restored all lost memories.
Completed the main story.
Cleared the game on Nightmare difficulty.
Filled out all monster details in journal.
Overcame Gruda's trial.
Opened every treasure chest.
Discovered every resource point.
Cleared all obstructed paths.
Endured all of Zara's tickle sessions.
Opened the door to the Temple of the Sun.
Played extensively as Frieda.
Successfully completed every quest.
Completed the Map of Celceta.
Defeated the ruler of the Great Forest.
Acquired both halves of the Mask of the Moon.
Enhanced a weapon or armor to its limit.
Played extensively as Ozma.
Found all of Mishy's hiding spots.
Arrived in the ruined capital, Elduke.
Befriended all animals.
Located the underground village of Danan.
Walked an extraordinary total distance.
Reunited with Eldeel at the Tower of Providence.
Played extensively as Karna.
Successfully arrived in the Primeval Lands.
Defeated two thousand enemies.
Played extensively as Duren.
Defeated a rare golden foe.
Resolved the polluted river dilemma.
Defeated Duren in one-on-one combat.
Solved the mystery of the missing villagers.
Played extensively as Adol.
Discovered a settlement in the Great Forest.
Achieved five hundred Excellent Kills.
Successfully used Flash Move fifty times.
Successfully used Flash Guard fifty times.
Achieved one thousand Aerial Combos.
Achieved five hundred Skill Finishes.
Successfully rescued the trapped miners.
Began your adventure in Celceta.