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