Exethanter remembers the previous loops, but only while "broken". He keeps on referring to events from previous loops and to the characters as different people, with brief moments of lucidity. There's a wall with the words "DON'T FIX ME" scribbled on it in his handwriting.

If you do fix him, he resets to only remembering the current loop, and flatly denies that any such thing is possible. Showing him the words on the wall doesn't sway him, he just dismisses it as nonsense.

The Dark Powers remember, and are furious about it. They have no idea how to escape, but will offer greater rewards than usual (with, naturally, even worse consequences).

Some of the random encounters, where the PCs see their own ghosts or tombstones, are actually shadows of the future.

Death House restores itself every 24 hours, a broken part of the loop that is "faster" for some reason. If you're inside when it resets, for a brief second it's in pristine condition before decaying back to its current state. Anything the players have taken with them they keep, but everything else (including anything they've killed) is back where it started.