Here is the full list of all 53 The Legend of Heroes: Sen no Kiseki IV -THE END OF SAGA- achievements.
Earned all achievements.
Completely filled the battle section in the notebook. (Besides the Extra category)
Completed the game on nightmare difficulty.
Reached the true ending.
Completed the finale.
Used 100 S-Crafts in battle.
Completely filled the character section in the notebook.
Opened every treasure chest.
Completed all quests.
Raised a master quartz to level 10.
Gathered all 5 lost arts quartz.
Won against all opponents in Pom! Pom! Party!
Gathered all 31 varieties of master quartz.
Achieved a Unity Grade of Unbreakable.
Achieved a Special Ops rank of A0.
Opened every trial chest.
Completely filled the fishing section in the notebook. (All 30 types of fish + Rod Lv. Max)
Took all landscape photos and reported them to Rex.
Completely filled the books section in the notebook.
Completely filled the recipe section in the notebook.
Completely filled the cards section in the notebook.
Spent the evening before the final battle with Juna.
Spent the evening before the final battle with Altina.
Spent the evening before the final battle with Musse.
Spent the evening before the final battle with Alisa.
Spent the evening before the final battle with Laura.
Spent the evening before the final battle with Emma.
Spent the evening before the final battle with Fie.
Spent the evening before the final battle with Sara.
Spent the evening before the final battle with Towa.
Spent the evening before the final battle with Alfin.
Spent the evening before the final battle with Elise.
Completed Eventide.
Forged a strong bond with Celine and Duvalie.
Forged a strong bond with Kurt, Ash, Elliot, Machias, Jusis, Gaius, and Crow.
Completed Act 3.
Raised any two characters to Link Level 7.
Used Brave Order in battle over 100 times.
Won 700 battles.
Completed Act 2.
Inflicted Break over 800 times.
Initiated 300 advantage encounters. (Including double and triple advantage)
Completed Fragments.
Used over 500 follow-up attacks in battle.
Completed Act 1.
Used Rush in battle 100 times.
Acquired over a million mira.
Earned an S-Rank on any act.
Won a battle with a tactical bonus of x3.0 or greater.
Used Burst in battle 50 times.
Won 100 battles.
Completed the prologue.
Infiltrated Orchis Tower.