Here is the full list of all 31 Deadlight achievements. It takes around 12-15 hours to unlock all of the achievements on Windows.
Finish the Nightmare mode
Make it to the end
Get 100% of Deadlight
Finish Randall's flashback
Find all of Randall's memories
Find all the IDs
Reunite with Stella
Beat the high score in Madness Mansion
Finish Randall's nightmare
Find Parker in the hockey arena
Beat the high score in Sport Daisy
Reload the revolver really fast
Roll to avoid lethal fall damage
Face someone from Randall's past in the Park
Find the first health expander
Follow the Ratman to his den
Finish Randall's dream
Perform a headshot
Get to the military control
Tackle an enemy
Perform a combo on an enemy
Push a zombie over a railing
Reach the junkyard
Execute an enemy
Kill an enemy with a single melee attack
Beat the high score in Raven Thunder's Rock Legend
Get infected by a friend on the leaderboards
Tackle a door
Escape from the warehouse
Find a page of Randall's journal
Survive a close encounter