Here is the full list of all 49 Atelier Ryza: Ever Darkness the Secret Hideout achievements.
Earned all trophies.
Became a Braver.
Activated everyone's Fatal Drive.
Defeated the Queen of Shadows.
Created a bottle with Gathering Synthesizer Level 51.
Obtained all recipes.
Defeated all 5 Great Elements.
Obtained the Revelation Book.
Created an item with Item Level 99.
Got Ryza's alchemy level to 99.
Wrote a record of every exploration.
Saw everyone move on to chase their dreams.
Created the Crimson Stone and saved Kurken Island.
Defeated the Queen of Darkness.
Got Ryza's battle level to 50.
Completed requests to get Peter to interview you.
Found all treasure chests.
Defeated the Noble Paladin.
Found and installed all Power Reactors.
Defeated the King of Storms.
Defeated the Savage Assassin.
Entered the Kurken Bunker.
Visited the Holy Tower of Pynnor and learn the truth.
Defeated the Mirage Master.
Created the Bomb Rod.
Defeated the Eternal Sculpture.
Installed the Multiplicauldron at the secret hideout.
Helped create Rasen Pudding.
Saved the goat you met on your travels.
Defeated the Shining Puni.
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.
Created the Bug Net.
Defeated the dragon at the old castle.
Created the Hammer.
Found one treasure chest.
Created the Fishing Rod.
Wrote a record of one exploration.
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.