Here is the full list of all 30 DUSK achievements. It takes around 15-20 hours to unlock all of the achievements on Windows.
Use cheats
Earn the 'Completionist' award in every level
Pick up a bar of soap in each level
Telefrag the Guardian
Kill Intoxigator while intoxicated
Neutralize Chomper
Reach E3MS
Reach E2MS
Find Dopefish
Find Lavender's secret
Kill an enemy by spinning your weapons
Watch the credits to the end
Complete all three episodes
Complete episode 3
Complete episode 2
Find 'Wife of Intoxigator'
Find a "You aren't supposed to be here go away" sign
Find Rachael's secret
Get past wave 20 in Endless Mode
Get past wave 10 in Endless Mode
Get past wave 5 in Endless Mode
Beat a level on 'Duskmare'
Earn the 'Untouchable' award
Earn the 'Pacifist' award
Beat par time in a level
Open Duskworld
Earn the 'Low Tech" award
Complete episode 1
Reach E1MS
Earn the 'Completionist' award