SILENT HILL 2

You can get 4 endings at once in one go. To do this, fulfill the conditions for the ending that you have not yet received during the first playthrough, and also collect all the items and fulfill all the conditions for the UFO, Dog, and Rebirth endings.
Having reached the Lakewiev Hotel, DO NOT pick up the Lost Memories book in the room of missing items and go through the location until you get the key to the third floor (drops out of the puzzle with the princesses). Make a manual save.
We go up to the third floor, open the door with the dog key and get the ending "Dog".
Load a manual save, go to room 312, activate the blue medallion and get the "UFO" ending.
We load the save, go through the game as expected, and get one of the standard endings.
We load the save again, pick up the Lost Memories book and go beat the final boss - we get the "Rebirth" ending.