Here is the full list of all 55 Ys X: Nordics achievements.
Proof of having thoroughly read Adol Christin's book “The North's Lost Paradise (Ys Nordics).”
Achieved 100% overall discovery rate.
Achieved 50% overall discovery rate.
Achieved 100% quest completion rate.
Achieved 100% intimacy completion rate.
Achieved 100% opening rate for 'Journal - People.'
Achieved 100% opening rate for 'Journal - Cooking.'
Achieved 100% opening rate for 'Journal - Battle.'
Achieved 100% opening rate for 'Journal - Fishing.'
Achieved 100% opening rate for 'Journal - Marine Life.'
Achieved 100% opening rate for 'Journal - Runestones.'
Listened to companions' conversations on the ship using the action menu.
Used adventure bento 10 times.
Used bottle medicine 20 times.
Thoroughly adventured with Adol.
Thoroughly adventured with Karja.
Achieved a total of 30 minutes in combo mode.
Held a maximum-level meal party on the Sandras.
Achieved a total travel distance of 300 Krimelye with Adol & Karja.
Achieved a total travel distance of 1,000 Krimelye with the Sandras.
Successfully performed Just Guard 100 times.
Successfully dodged 100 Speed Attacks.
Achieved 99CHAIN as the maximum Skill Chain.
Used Mana Action 2,000 times.
Used EX Armament 100 times.
Used Mana Sail 300 times.
Achieved 30 minutes of Mana Barrier activation.
Defeated 1000 enemies.
Defeated 500 Greegers.
Defeated 300 enemy ships/barrier pillars.
Reached the maximum depth of 'Release Line.'
Activated all Mana Abilities (10 types in total): Valor, Fortitude, and Optimism.
Activated all 10 types of Dark Mana Abilities.
Enhanced all the strongest equipment (2 strongest weapons + 2 strongest armors).
Implemented all 'Improvement & Training Plans' for the Sandras.
Achieved level 10 for maximum level of recapture tension gauge.
Cleared any recapture battle with an S rank rating.
Achieved 100% recapture battle completion rate.
Destroyed all disguised merchant ships. (Total of 3 ships)
Gave all the Pikkards to Sash and completed the Pikkard collection.
Defeated the strongest Greeger, Vermoz.
Achieved 100% rescue rate for the Karnack residents in need.
Reached the epilogue on Nightmare difficulty or higher.
Started a new adventure.
Cleared the Prologue “Assault.”
Cleared Part I “Karnack.”
Cleared Part II “Shield Brothers.”
Cleared Part III “Towards the Light.”
Cleared Part IV “White Darkness.”
Cleared Part V “The Smoke of Counterattack.”
Cleared Part VI “Mirror of the Sky.”
Cleared Part VII “The Great Battle of Flumen.”
Cleared Part VIII “Lila.”
Cleared Part IX “The Sea of Beginnings.”
Cleared Part X “The Northman’s Lost Paradise” and reached the epilogue.