time warping rat infested dungeon

[Radon26]

so, what happened.

entered the old forest-4
cleared half of it
entered and cleared the rat dungeon
left the dungeon and back to forest
take a few steps
leave the game

next day

load the game
destroy the wild life
kill the boss
equip frost threads
exiting the lvl (finding the exit)
"its a hole in the ground, have i been there?"
enter the dungeon again
"oh right, that's where i got the skull"
leave the dungeon
"uh..."

i found the lvl in the same state as it was when i left the dungeon the previous session, half explored.
then i continued exploring and killed the wrath wood for the second time.
going to check if i can do that again

==============edit===================
nope, did not warp the second time. the saving and quitting may be a vital component.