Here is the full list of all 49 Atelier Ryza: Ever Darkness the Secret Hideout achievements.
Earned all trophies.
Activated everyone's Fatal Drive.
Created an item with Item Level 99.
Wrote a record of every exploration.
Wrote a record of one exploration.
Created a bottle with Gathering Synthesizer Level 51.
Became a Braver.
Got Ryza's alchemy level to 99.
Defeated the Queen of Shadows.
Defeated the Noble Paladin.
Defeated the Eternal Sculpture.
Defeated the Mirage Master.
Defeated the Savage Assassin.
Obtained all recipes.
Defeated the King of Storms.
Obtained the Revelation Book.
Completed requests to get Peter to interview you.
Found all treasure chests.
Defeated all 5 Great Elements.
Found one treasure chest.
Got Ryza's battle level to 50.
Saw everyone move on to chase their dreams.
Created the Crimson Stone and saved Kurken Island.
Defeated the Queen of Darkness.
Found and installed all Power Reactors.
Entered the Kurken Bunker.
Saved the goat you met on your travels.
Visited the Holy Tower of Pynnor and learn the truth.
Helped create Rasen Pudding.
Defeated the Shining Puni.
Created the Bomb Rod.
Installed the Multiplicauldron at the secret hideout.
Helped Empel regain his former strength.
Spent the night camping in the Underworld.
Laid eyes on the Underworld.
Installed the Gathering Synthesizer at the secret hideout.
Learned about the history of Ryza and the others.
Installed a Power Reactor at the secret hideout.
Defeated the dragon at the old castle.
Created the Bug Net.
Created the Hammer.
Created the Fishing Rod.
Built a secret hideout for everyone.
Witnessed the rise of a strange beast.
Created the Woodcutter's Axe.
Attended a tea party with Ryza and Klaudia.
Created the Reaper's Scythe.
Synthesized for the first time.
Visited the mainland for the first time.