This combined animation/Muppet show from Jim Hensen Productions gets an extra half star just
because the main characters are all dogs, one of who explains how a time machine has
completely altered Dog City in the episode “Future Schlock’ (12 Nov 1994).
Due to the use of a time machine, events were changed in Dog City’s past, which
naturally affected Dog City’s future, which was Dog City’s present, of course.