It’s real, but there’s more than a little forced perspective in that shot. Some more pictures here, like this one:
He weighs about 30 lbs.
Maine Coon Cats are seriously large. There’s a bit of forced perspective in that shot, but it’s not outrageous. Maine Coon cats can grow up to 34 lbs, which puts them in the middle of the size range for a Lynx or Bobcat.
I originally thought of them to refute the point that making smaller animals larger necessarily makes them more dangerous. Sometimes animals are dangerous because they are small and fearful. The Maine Coon Cat is the largest domesticated cat, and also considered to be one of the most gentle. A bear is more likely to leave you alone than a wolverine, which may feel more threatened by you.
Most poisonous insects want nothing to do with you, and often bite because they get stepped on or cornered by someone who didn’t see them. Making them bigger might just make them more avoidable.
But I do not want to meet an upsized Camel Spider. The current ones are upsized enough.
A forty foot Canada goose.
I said dangerous, not Apocalyptic.
That gives the legendary “I’ve been slimed!” anguished cry a whole new dimension of awfulness . 
Imagine goose turds the size of hay bales and the consistency of wet oatmeal.
Giant isopods—roly polies as big as small cats—are pretty horrific. Yet another reason never to go into the ocean.
Naw, they’re adorable!
Now I want a giant isopod plushie.
Eff. That.
I bet with enough artistic license you could make that plushie downright cute. OTOH, the kids raised with one would grow up to be ruthless cannibals, so there is an upside to the experiment.
I happen to share a home with a 2 year old Maine Coon. Yes, they are large cats (George is 18 lbs in this pic, the other cat is 8 years older than him):
Yes, they are often called Gentle Giants. They are still cats and they still react like all cats do when frightened, startled or annoyed.
Maine Coons are also 3/4 floof. George’s mane is already floofy enough that when I poke his neck, I bury my entire outstretched finger while reaching. Next year his mane should bury my entire hand.
That fabulous white cat is well known in some circles. He is a show cat and benefits from professional grooming before his pics, his fur has been floofed to the max AND there is a lot of perspective and posing with small people involved in his glamor shots.
He is stunning, though!
He’s also a good fit for Cats That Look Like Ron Perlman.
Thank you for that. So many beautiful cats!!!
The other photo from the Wikipedia article reads:
A frontal view of Bathynomus giganteus , showing its large, highly reflective compound eyes
Imagine walking along a deserted beach at sundown with your flashlight and seeing those eyes reflecting back at you.
Mmm-mmm-mmm. Good eatin’!
“We’re gonna need a bigger deep fryer”.
It occurs to me that if a giant ground sloth could reach an estimated weight of four tonnes, than an ape could be that large too. So not King Kong sized but Mighty Joe Young sized, which would be plenty big enough.
Amoeba.
I guess that’s how the incredible shrinking man survived (as long as he did, we really don’t know what happened to him in the end).
The normal ones are described as “Cobra chickens”.
“Godzilla chickens.”
What about foot long mosquitoes, if they have not been mentioned?