I don't know if this comes under bugs but the first thing that comes to my mind about scary insects is lizard.
I hate them! Yuck Yuck Nasty! Seeing one is enough to give me goosebumps all over my skin. I guess this fear of lizards is because of my childhood experience when a lizard fell over my head. Devastating! Truly!

    Parasites that dig into your skin are the most frightening. Imagine a worm longer than your body spread throughout your innards. They can get in through your ear, mouth, nose or any hole and lay eggs. If you’re writing a novel it would be a terrifying scene to picture a gigantic worm chewing its way out of a body after it’s done growing and leaving larvae that attack the party in their sleep after the mother escapes.

      23DN4L 😱😱😱 ... props to you for being clear-headed enough not to panic. I would have screamed and jumped around like a headless chicken while trying to pull it off.... Now I'm getting goosebumps

        23DN4L a tick could dry up humans if they are larger, same with mosquitoes. Fleas have this energy storage thing that could multiply their speed. That's why they could easily jump 100x their height, or flip a coin if you put it over them.

          23DN4L there are also obvious ones like black widows, tarantulas and bullet ants. Black widows and bullet ants could already kill humans from their original size.

              How about attacked by mob?
              Mob of insect is more scary than one insect with OP defense

              checkm8 0.0 I read the entire list and oh man oh man. Thanks for these. I definitely wanna use them in my story; especially the waterbug. Wink wink, you might find it in a chapter soon.

              But ugh that scorpion arachnid will haunt my dreams tonight. Thanks a lot. (Sobs)

                  bachingchung
                  You’ve listed a lot of good creepers.
                  Fun Fac: The black widows favorite form of birth control is eating their mate after first pregnancy. #tilldeathdoyoupart

                  Bullets ants are the cowboys of the wild world shooting people up with their sting. They don’t even need a gun and hands. Them and fire ants are the reason I’m afraid of all ants.

                      UnderTaker26
                      Indeed! That would be horrific! I almost want to wear earmuffs while sleeping now.

                          Jinu_June Lizards can be scary. I don’t know if it’s a lizard, but Komodo Dragons creep me out. Big enough to eat me too.

                              23DN4L centipede! with its many legs, no matter how fast you run, it still can catch you Muahahaha

                              I can recommend a manga with similar type with your story: Kyochuu Rettou
                              That manga also tells about a bunch survivor from the wrecked ship that landed on a mysterious island that filled with giant insect

                                  Jinu_June there's only one place where comodo dragon can be seen in their natural habitat, or else you can only see them in certain zoo, like zoo in Rotterdam, Sydney and Singapore 😊

                                      23DN4L Anyway komodo dragons are not common as garden lizards right? Then how could you get frightened so much? It is rare to have it around your surroundings right? There is little chance of it coming after you. But lizards can get to you easily.

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