Solution:This is the longest achievement to complete as it requires multiple playthroughs. I'd recommend rewind over the original thanks to quality of life improvements speeding up the process. Each ending has a series of requirements to complete it.
- Learn about the clock tower: You must either run into Lotte in the underground tunnel or examine the books on the desk in the religious study.
- Learn about Mary Barrows: You must either find Walter Simpsons corpse or use the ham in the shack to learn the truth about Mary Barrows.
- The elevator: Towards the endgame, you'll enter an elevator. Only floors 2 & 3 are of any consequence.
- Your friends: Different endings play out depending on who is alive. Unfortunately, Lotte will always die.
- Freeing the crows: The crows can be found in the cage room. The location is different for each playthrough. It is one of the interchangeable doors in the west wing. In original mode, the key is on the table inside the cage room. In rewind mode, one needs to kill the undead to obtain the cage key. Use the cage key on the right cage to free the crows.
With that out of the way:
S: - Learn about the clock tower
- Learn about Mary Barrows through the sealed room
- Elevator Floor 3
- Laura or Anne is alive
- Free the crows
A:- Learn about the clock tower
- Learn about Mary Barrows through the shack
- Elevator Floor 3
- Laura or Anne is alive
- Free the crows
B:- Learn about the clock tower
- Learn about Mary Barrows
- Elevator Floor 3
- Laura & Anne are dead
C:- Learn about the clock tower
- Learn about Mary Barrows
- Elevator Floor 2
- Laura & Anne are dead
D:- Learn about the clock tower
- Don't learn about Mary Barrows
- Elevator Floor 2
E:- Learn about the clock tower
- Don't learn about Mary Barrows
- Elevator Floor 3
F:- Don't learn about the clock tower
G:- Escape with the car after Laura & Anne die
H:- Escape with the car after Laura or Anne die
This might seem like a lot, but there are a few ways to speed this up:
- Endings G & H can be obtained at most points in the early game. Pick one of the endings you'll be going for, & rush for the car first chance. After the ending plays, select continue game & keep playing.
- Ending E should be obtained before Ending D. After the ending plays, select continue game & you can select another floor to obtain Ending D. This cannot be done in reverse.
Good luck!