Here is the full list of all 71 Golden Light achievements.
Complete 20 floors total
Buy a key from Pile of Meat
Complete 5 floors without dying
Meet Rose for the first time
Find 3 Golden Meats total
Kill a monster with a Shotgun
Complete any floor without using your weapons once
Finish any floor without taking damage
The Gut hates you
Make 100 gold
Make 200 gold
Make 500 gold
Make 1000 gold
Kill 100 monsters total
Eat a fire item
Eat a poisoned item
Kill a monster with a Revolver
Destroy 50 walls total
Kill a monster with a Vein Whip
Kill Eye Taker
Burn a monster to death
Kill a monster with a Pipe
Complete 3 floors total
Kill a monster with a pistol
Read a special note
Find your first Golden Meat
Bring a rose to Val
Die
Kill She in the flashback
Kill a monster with an Axe
Kill a monster with a Tommygun
Kill a monster with a Map
Put your hands into the talking toilet
Lose an eye
Kill Castle directly
Throw 500 gold at Son
Buy a key from Golden Eye Taker
Kill anyone with your Huge Chin
Find a multy barrel shotgun
Save her
Kill Carre directly
Kill Needles directly
Kill Maneater directly
Kill Gut Divers directly
Collect Marv, Third Lung and Pulp mementos in one run
Kill Meall directly
Complete 50 floors total
Complete 100 floors total
Kill your Meat Bro in Co-op while having Traitorous Bastard memento.
Collect 25 keys total
Collect Huge Chin and Nose with Teeth mementos in one run
Ressurect your Meat Bro in Co-op
Complete 1 floor in Co-op
Kill an Eyetaker with Meat Spear
Complete 20 floors without dying
Destroy a wall by eating an item
Complete 500 floors total
Kill 500 monsters total
Kill 1000 monsters total
Enter the White Room on Meat War
Enter the Field Room on Meat War
Enter the Torture Room on Meat War
Enter the Murder Room on Meat War
Enter the White Room on MEATZONE
Enter the Field Room on MEATZONE
Enter the Torture Room on MEATZONE
Enter the Murder Room on MEATZONE
Get every memento and open the final door
Enter the Val Room
Enter the Val Room on Meat Zone
Kill Scourge directly