Here is the full list of all 18 Lost Nova achievements.
Expensive headwear.
Witnessed the righteous fury of Sir Corv.
Attended a concert of three best friends.
Reached the lowest level of the Silkgem Mines.
"What a novelty you are."
Made a small friend.
Quadrupled the opportunity for science.
Filled the museum with priceless artifacts.
Pet every bunny in every town.
You fixed your ship, saved the world, and helped out a giant worm. What's next?
Shipping and handling not included.
He pinch.
Planted flowers.
"Come on down to Brian's Blasters: you'll love the way you blast."
Picked roses for the princess.
Pumpkin!
Pushed a block where it needed to be.
The theme of the game.