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