Here is the full list of all 30 Deadlight achievements worth 400 gamerscore. It takes around 6-8 hours to unlock all of the achievements on Xbox 360.
Beat the high score in Sport Daisy
Get 100% of Deadlight
Find all of Randall's memories
Find all the IDs
Beat the high score in Madness Mansion
Beat the high score in Raven Thunder's Rock Legend
Make it to the end
Finish Randall's flashback
Reunite with Stella
Finish Randall's nightmare
Find Parker in the hockey arena
Reload the revolver really fast
Face someone from Randall's past in the Park
Roll to avoid lethal fall damage
Get infected by a friend on the leaderboards
Find the first health expander
Follow the Ratman to his den
Finish Randall's dream
Perform a headshot
Get to the military control
Push a zombie over a railing
Kill an enemy with a single melee attack
Tackle an enemy
Reach the junkyard
Perform a combo on an enemy
Execute an enemy
Survive a close encounter
Tackle a door
Escape from the warehouse
Find a page of Randall's journal