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