If you start your file even earlier, you will simply be starting your file normally. If you start your file later, then you will not end Back in Time and you can try again.
Bed Trick is caused by your spawn type when sleeping in beds to be locked to value 0, which is the spawn type used to respawn you at entrances.
Sometimes, performing bed trick will crash the game instead. When this happens it means you attempted bed trick in a house that does not contain the room number for the area you're attempting to load. All Skyloft houses only have a room 0, and thus these houses can only load a room 0 (for exemple, this means the first room of a dungeon, or only behind the temple in the Sealed Grounds area). However you can perform bed trick inside the Knight Academy using Link's or Fledge's bed in order to warp to rooms having IDs 0,1,2,3,4,5 or 6. Remember that to do so, you need to enter the Academy with a file that does not have the Hero's Tunic, then update the story information from a file that has the Hero's Tunic (by opening Link's dresser), and then sleeping in the bed. There is however a downside and it's that the file you must start for bed trick inside the Academy needs to not have the Hero's Tunic, because sleeping in the Knight's Academy with the Hero's Tunic loads a layer that crashes in Back in Time.
File Duping Teleportation
After starting your file when performing bed trick, the Title Screen logo will appear for a split second, with Link either opening the door to the house you entered (if your file is saved with its last entrance being a door opening animation) or just standing at the origin of the map. If you open the Splash Screen during this split second and before the loading transition ends, you can copy all of the information from file 3 over the file you started, but still spawn at that file's last entrance point. This is called a File Dupe.
This glitch is useful because it allows you to teleport your run file (that needs to be saved on Slot 3 for this trick) to any place File 1 and File 2 last entered. This trick is similar in use to a BiTSave in the sense that it allows for teleporting your file, but whereas a BiTSave is limited to Skyloft and a few areas of the Surface by going to Faron in BiT, this method works for any area where you can save. Simply put the file that's making game progress on slot 3, perform bed trick by starting the file saved in the area you want to warp to frame perfectly by sleeping from day to day in BiT, and open the splash screen when it appears. File 2 will now be a perfect copy of File 3 progression-wise, but you will still load where File 2 was saved beforehand.
Stale Entrance Warp
Bed Trick can be used in some scenarios to warp to entrances you are normally not able to access. To do so, you must first trigger an entrance in some room. Then you need to change room without triggering any entrance, and save in another room. The saved entrance value will still be from earlier, and performing bed trick will now load you in the room you were saved at but with the last entrance value triggered. This causes you to spawn at entrances you've never been before.
One use of this is to spawn near the Ancient Cistern Boss Entrance. Go into the Ancient Cistern Basement by going down the rope first. This is entrance 2 in room 4. Then, use the main statue to climb back up to the main room, which is room 0, and save at the entrance statue. Now performing bed trick will load entrance 2 of room 0, which is near the boss.
Note that you cannot die to respawn in another room, as otherwise the game will grab back the entrance value used to enter that room.
Bed Trick Clipping
After a bed trick, the game will load you at your last entrance, but without setting your respawn coordinates and angle properly. This means that dying after a bed trick will make you respawn at the coordinates of the statue you saved at before the bed trick, but with the animation of the entrance used to enter the area. Some of these entrance animations make Link be in a no-clip state, which allows him to clip though walls.
This does not work with all entrance animations, such as the landing at a statue animation. Landing at a statue does not work because if you die after landing at a statue you respawn at the statue without the animation playing, contrarely to dying after entering a dungeon door entrance for exemple
Last updated 11/30/2020