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