You'd think that a show like this, would be immune to Nightmare Fuel just because it's centered around kids, right? Wrong!
- Some of the oddness, namely the stuff involving giant monsters or undesired transformations, are pretty creepy to contemplate even if the show downplays them.
- Bad Luck Bears: Some of the bad luck The Bears were cursed with when they had 13 of something could have been some serious health hazards.
- My Better Half: Otto getting his face entire body chopped in half by Symmetric Al. On a kids show. We're lucky this is a kids' show, or Otto could have been bleeding from his remaining half. Or worse, died from blood loss! Thankfully things turned out well in the end. Click the link... if you dare! ◊
- The effects of both "Take Away Four" and "Gotta Add Four" are actually somewhat terrifying. The former could have done something like vanish the wheels from a car or other vehicle while it was in motion, and the latter was shown to add 4 suns in the sun, which could have cooked the Earth!
- Oscar and the Oscarbots: The scene towards the end where the 25 Oscar-Bots transform into one giant and scary robot. It's so scary, we're not even allowed to see it onscreen.
- Skip Day: When Olive ended up with an odd disease of the skips, it caused her to skip steps (and actually skip). But the disease quickly proved to be dangerous, such as when Olive went to go parachuting, but skipped the step of putting on a parachute. Before she knew it, she was falling from several thousand feet screaming for her life. Just imagine what would have happened if Otto hadn't shown up and saved Olive...
- The Perfect Lunch: The Featherites in general. Not only are they extremely picky about their meals and cause oddness if their demands aren't met, they've also mentioned they had five mouths.—One on their their main faces, and four on their wings. Thankfully the four additional mouths were only heard, and were offscreen. Yikes!
- Agent Obfusco: Olive and Otto were re-taking the Odd Squad test to keep their jobs. One of the tasks was gadget identification. Olive identified the pudding-inator right away and suddenly Obfusco — the mentor of the test- zaps Otto with the ray, turning him into pudding. Yes, it was part of the test, and yes, Olive guess what the un-pudding-inator was, but what if she guessed wrong? At best, Otto would've transformed into something else and been able to change back, but at worst, Olive could have chosen the disintegrate-inator and killed her partner! Jesus! Thank goodness Olive was able to figure out which gadget the un-pudding-inator was.
- Trials and Tubulations: All the odd creatures Olive and Otto encounter in Sector 21.
- The Slow Motion Forest that would take you a lifetime just to get to your location.
- The Laser Chickens.
- The tentacle man pictured above.
- And then there's the forest coming to life and attacking Olive and Otto when the sun when down.
- Training Day: Odd Todd's "take that" strike against the Squad - unleashing the pienado indoors - is pretty disturbing when you realize that had Olive not sealed the container, it might have destroyed headquarters. Since most, if not all, of the staff were downed by the flying pies, they might have been unable to escape when it collapsed.
- Extreme Cakeover: The Cake Virus can be horrifing once you stop to think about it. The virus is completely unpredictable and goes after a group of people with a specific trait in common. If someone's unfortunate enough to catch the virus, the victim will have to watch in horror as their body parts turn into icing, and they continue to transform until they go full cake. The victim will then be unable to do anything, and can only pray that nobody will try to eat them. Seriously, this sounds like something out of a horror movie!
- The Cherry-On-Top-Inator: Oona's Sanity Slippage throughout the episode can come off as pretty unnerving, especially to younger viewers.
- The Scientist: It seems as if everybody in the world has been turned into exercise equipment. Even the villain responsible must have done it to themselves (accidentally?) since nobody is seen trying to break into or contact HQ. And either there's no Odd Squad Space Station, or that crew has also been turned into exercise equipment. Oona seems unconcerned about investigating.
- World Turned Odd: The Bad Present where Ms. O (Oprah) gets fired from Odd Squad, Olive and Oscar never become agents, Odd Todd succeeds in taking over all Odd Squads, and all Odd cases get unsolved. And to think, it all happened because Oprah failed that one Ms. O test.
- Odds and Ends: How about the fact that a seemingly harmless child (Ohlm) was actually an evil mastermind in plain sight, bent on destroying Odd Squad, and stealing their plans to villains to help them break in? Good luck sleeping after that episode.
- The Daves in general can also qualify. Those creatures are literally destructive forces of nature. If those creatures had succeeded and their plan, and stuck around long enough, the entire planet would be in grave danger. Based on Oona's description of the Dave's traits, those little creatures are not to be messed with. They nearly destroyed the city. The fact that they're constantly doubling doesn't help matters.
- The villain Shelley Catessan is one of the most cruel yet. In "The Sandwich Project," she takes great delight in turning the OSMU members and random civilians into sandwiches, and she cackles at the thought that they'll be sandwiches forever. That's pretty much the same thing as murder since she wants her victims to be lifeless objects permanently.
- The Shadow can also qualify. "Slow Your Roll" had her hacking into the van and attempting to drown it in the Lake of Goo. However, the Mobile Unit agents are inside of the van, and considering she changed the locks on all of the doors to prevent them from reaching the main control room (never mind the fact that Opal, the agent she has a vendetta against, wanted to stay in the van despite the risks), her drowning the van essentially means that she's planning on taking the agents down into the lake with it. Yep, that's right, this Enfant Terrible wanted to commit an act of murder via drowning. It especially doesnt help that said Enfant Terrible turns out to be the sister of Opal.