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