The first problems that come to mind when you think about time travel probably involve the fabric of the universe or the state of your own existence. But those aren't what would make time travel just plain old irritating.
10 Little Things That Would Make Time Travel Super Annoying
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Video. Mark Ruffalo wasn’t joking.
The abstract nature of cartoons means you can take some liberties with such trifling concepts as colour and anatomy when drawing characters. Unfortunately, bringing said characters out of the abstract and into reality often ends with... well, why don't I let this terrifying 3D version of Homer Simpson explain?