An example of gore would be a scene that depicts a massive injury such as cutting open body parts to the point where in shows innards, or cutting off body parts.
So, using a murder mysteries as an example: A murder scene like in the first season of Dexter (cutting off body parts) or Hannibal (cutting open body parts) would be gore, but a murder scene in BBC's Sherlock or Hercule Poirot would not be gore.
Blood can be shown.
The submission guideline is to encourage video creators to be comfortable to livestream playthroughs without accidentally stumbling upon gore.
I hope this helps answer your question.