Rollback

[Synopsis]

Hi everyone. First of all I'd like to apologise if this problem had already been solved before. I found multiple checkpoint-related threads but I didn't find solution to my problem.

Problem:
Let's say I have a straight hall running from west to east. In the eastern side of the hall is a spawn point. Somewhere in the middle of the hall is an area that triggers a cave-in in the western side of the hall (preventing player from escaping to previous room) and it also triggers a grunt in the eastern side that automatically goes after the player.
If the player died, I want him to spawn at the very beginning of the room, before the cave-in area. Problem is I want all events that happened after the player entered the room till he died to be resetted. (Therefore all flashbacks, locked doors, lit lamps, used tinderboxes, cave-ins are returned back to their initiate state.

I sincerely hope it's possible.
Thanks in advance.

-Synopsis