Here is the full list of all 27 Harold Halibut achievements.
Update Mareaux about every step of the search for the Blue Rock.
Participate in the station jog.
Try out Slippie's ski slope.
Talk with everyone about the exchange.
Complete the Notebook.
Untangle the story of the brothers.
Read and deliver all of Buddy's letters.
Complete the game.
Enjoy the game at a leasurely pace (more than 15 hours play time.)
Complete Chapter 6.
Clean all of the graffiti.
Complete Chapter 4.
Support Captain-at-large Zoya during all walks of life.
Complete Chapter 3.
Complete Chapter 2.
Complete Chapter 1.
Complete Chapter 5.
Attempt to leave the All Water Office 3 times.
Listen to all of the gossip at Gertrude's Bierzone.
Watch TV for 10 minutes.
Convince Warren to move Water Wieners to the Cave.
Help Slippie set up in the Energy Disctrict.
Try to pick up the sample directly from Brigitte.
Listen to the Announcer under the shower.
Play Rapid Fly Zone Force for 2 Minutes.
Watch Onat's stage performance.
Make your first trip on the All Water tube.