Here is the full list of all 21 Humans Must Answer achievements.
Take the Chicken's Way Out
When you do things right, people won't be sure you've done anything at all
Die as a hero, live as a villain
Collect 100% of the golden eggs
Defeat The Ankh
Beat 20 levels to 100% (Gold status)
Collect 75% of the golden eggs
Defeat The Martian Drill Laser
Defeat DNA
Beat 15 levels to 100% (Gold status)
Upgrade any weapon to max level
Collect 50% of the golden eggs
Beat 10 levels to 100% (Gold status)
Obtain the support weapon
Defeat Sheriff Gilgamesh
Collect 25% of the golden eggs
Beat 5 levels to 100% (Gold status)
Collect 10% of the golden eggs
Kill The Starbound Penguin
Beat 1 level to 100% (Gold status)
Pass border patrol