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