People who watch garbage shows like the cardashians and think they are awesome frighten me.

Trump

Two tongued Politician, White Coated Physician, Black Robed Judicrant, Skin headed Guntoter, White Robed Crossburner, Blindeyed Lawenforcer, Songsinging Biblethumper.

Donald Trump

Republicans

As I say all the time, humans are the worst.

an orange racoon hat on a human, Such as trump

Religious nut cases. Watch out for the God Virus, Ive seen too many fall for this trap.

Actually, no animal, bird, insect, reptile creeps me .. only the homo sapien I detest collectively.

Dudes wearing a witch's hat.

If I had to pick one, I'd have to say botflies. While interesting, they're creepy as hell. The larvae are parasitic to mammals, including one species that is known to infest humans. They burrow into the skin where they grow, eventually emerge, and drop off ready to pupate (which they do in soil.)

Snakes only because I was bitten by a rattlesnake when I was three and I can't remember much about being three, but I remember that day very well. I saw the rattlesnake while playing in my backyard and I decided it would be fun to pick it up. Not a good move at all.

Japenese Giant Crabs... they are alien as fuck.

Cockroaches.

People

Homo Sapiens

Humans. Capable of remarkable acts of goodness but also horrifying evil.

Roaches. I am a rational, logical person, yet roaches can make me lose my composure in a second. I think it's the idea that if you see one, you imagine thousands and they move so damned fast!

I tend to be the one who likes the critters most other people think of as 'creepy'. I worked at a reptile zoo for nearly a decade, and now my research focuses mainly on arachnids. I share my home with 2 parrots, 13 snakes, 1 gecko, and around 80-90 arachnids (mostly tarantulas), and am usually referred to as the 'crazy spider lady'!

Centipedes used to wig me out more, but I'm getting better with them, though earwigs are still my NOPE.

It looks like spiders, snakes, humans, and cockroaches are at the top.
Surprised no one mentioned clowns, wait a minute people did say they are afraid of Trump.
He is really the scariest thing because he affects all of us! What an orange-faced clown!

Roaches, but just the German ones. Madagascar riachs are cool. I love spiders, snakes and have had pet rats

swimming with sharks bigger than me...

Actually, as long as I don't have to physically interact with them, they are all good. Even the Man of War, which I fear beacause one burnt me once while swimming, is beautiful to look at.

Cockroaches really creep me out

Humans
No other creature has devised so many ways to kill or takes such pleasure in it.
No other creature has bent nature for profit at the expense of its fellow species and all other species.
No other creature hunts, kills, rapes, and mutilates for the sheer rush of pleasure it gets from it.
No other creature has serial killers, mass murderers, spree killers, Despotic Rulers and industrialized murder.

ALL other creatures pale in comparison.
Even in your example it was a human who was using rats as a weapon, yet you fear the rat. Go figure.