Someone Asks What's The Scariest Thing In The Ocean That Has Photo Evidence, And 27 People Deliver

Bobbit worms. They look like something out of a h**l dimension, they range from 4 inches to 10 FEET long, and their jaws are so powerful that they can snap fish in half. And what’s worse about them compared to a lot of the answers in this thread is that *you can end up with a Bobbit worm in your at home saltwater aquarium by accident*. They like to live in holes of large rocks, which are also popular among aquarium enthusiasts to use as decor, or hide inside the substrate at the bottom of an aquarium. As they are ambush predators who are mostly active at night, you probably won’t figure out that there’s one inside your aquarium until you notice fish have started to go missing. These worms are almost impossible to get rid of out of your large aquarium rocks, as they can cling so tightly to the hole they’re in that you can’t pull them out. They’re also really good at hiding in small spaces. If you tear the worm apart trying to get it out (which is pretty easy to do) the leftover part inside the rock hole can regenerate into a new Bobbit worm. ETA: As to why an aquarist doesn’t just boil the rock/bake the rock before putting it in their tank to prevent Bobbit worms- The rocks the worms hitch in on are called “live rocks”. These rocks are from the ocean floor and contain microorganisms, bacteria, algae, coral, and invertebrates that help make the tank water healthy and stable. So anything that would [end] the worm beforehand would also [end] all the beneficial organisms on the rock, thus defeating the purpose of buying an expensive live rock. By the time they’ve figured out a Bobbit worm got into their tank it might have been weeks or months since the rock got put in (as Bobbit worms hide during the day and hunt at night). At that point the worm could be anywhere in the tank.

Hands down Sea Lampreys. These creatures haunt me. They are the most horrific thing I've ever seen 

Shape shifting creature found in the bottom of the ocean.

Marine biologist Bill Austin has suggested it is likely a comb jelly (ctenophore).

Great Lakes shipwrecks. For some reason, they are creepier when they are more perfectly preserved. So friggin cool but also scares me

I submit for your viewing pleasure, or horror, The gulper eel

A giant squid. One of these can supposedly take down a small whale (not an adult sperm whale… those actually feed on these guys). A person would barely be a snack.

Great white sharks. Let’s not overthink this.