Full list of all 23 Going Under achievements worth 1,050 gamerscore. It takes around 12-15 hours to unlock all of the achievements in the base game on Xbox One.
The base game contains 20 achievements worth 1,000 Gamerscore, and there is 1 DLC pack containing 3 achievements worth 50 Gamerscore.
Unlock all skills.
Kill a Hungry Box.
Complete Swomp's mentorship.
Complete Fern's mentorship.
Complete Tappi's mentorship.
Complete Kara's mentorship.
Kill a power loader with Exit Strategist
Complete Ray's mentorship.
Save the World?
Defeat Vested Marv.
Obtain Hover Hands' Share.
Obtain The Caffiend's Share.
Obtain Hustlebones' Share.
Go Under.
Get cursed 13 times.
Obtain The Toxic Mask.
Open 100 delivery cubes.
Obtain The Grim Ledger.
Obtain The Mana Press.
Meet Your Coworkers.
Complete the Rolodex
Complete The Impostor's final test.
Win a run in Impostor Mode.