These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
The ending of "Wendigo" leaves it up to interpretation whether the titular monster was truly supernatural or simply a human who went crazy.
Base Breaker: Whether the Enigma Corporation is an improvement to the show or the old continuity-free format is better.
Complete Monster: While the monsters normally have a natural reason for attacking humans, food, protecting their turf, or revenge, the Poltergeist crosses the Moral Event Horizon, not only did he kill his own family in life, he keeps telling the heroes to leave and right as they're about to do so, he locks the door and proceeds to kill them all in cold blood, taunting the last guy with the voice of a child to lure him in, then kill him.
The Evil Poacher from Bigfoot. He not only wants to kill the lead character, the way he talks to her implies that he wants to rape her. Thank God Bigfoot came when he did.
Narm Charm - Sometimes, the episodes fall flat on their faces (often with blatantly supernatural creatures). Other times, they manage to hit some actual tension (one featuring the giant monitor lizard Megalania and the Bigfoot episode) in the direction. Watching someone suffer from Blood Poisoning is pretty terrifying since that sort of thing can happen when bitten by certain venomous animals. Still, nothing can grant forgiveness of the terrible acting in the opening of Lizardman.
Nightmare Fuel: Sometimes, the show manages to break out of Narm Charm and actually work - Death Raptor, Vampire, Wendigo, Alien and Skin-Walker are genuinely scary.