Fictional Creatures/Characters that Would Have Destroyed the World or Effected the Environment

This would be the worst invasive species coming from the fictional world, outcompeting native real life carnivorous species, turning their human victims and other similar species into vampires through blood transfusion and/or being bitten. They would cause overpopulation on Earth due to their immortality and such. These nonnative now-real vampires would most likely come from the Seraph of the manga and/or anime due to not being harmed by religious artifacts and have devices that keeps them from getting burned by the sunlight. I don't want to live forever with or without a soul (if souls were real) and I don't want to become a vampire.

I actually like vampires! But I don't want to be afraid of some weird ass creature biting my neck in the middle of the night!

This is scary. I don't want to become an evil vampire and live forever.

These animals would be human species that evolved to turn into wolf-like apes either with or without a tail, depending on a subspecies. They would likely come from movies like Van Helsing, Underworld, etc due to the some of these movies being popular and some person wanted to make them real. If they suddenly became real, they would kill many populations of humans in poor countries due to their large almost bottomless guts and carnivory, they would also outcompete native real life wolves, big cats, and even bears.

I know this is only a character, but he would damage the environment and/or devastate the country/ continent/world due to his superpowers such as darkness powers, near-invincibility, etc. He would most likely be considered a threat to humanity, especially since he has hatred against humanity, using his powers to harm/kill people, etc. If he felt lonely, he would have developed the ability to turn his victims into his clones, which may sound unlikely and weird, but it is possible since Bass.EXE seems lonely in the series.

Just like Bass.EXE, Elecman.EXE may just be a character, not a species, but he would cause almost as much trouble as Bass.EXE if he came from some episodes/games where he is evil and not a protagonist. He would probably steal electricity from power grids and other major energy sources humans have, using them as his weapons against humanity. Because of his high amount of electricity, his powers would most likely be much deadlier than that from the electric eels.

This is almost always a cliche since most series/movies have zombie apocalypse, where zombies infect the world and human populations around the world dropped until humans are endangered. This could happen if they suddenly became real unless humans already made anti-zombie protection vaccines that protect human populations from dying from zombies and their viruses.

As how the first Jurassic Park film have shown, these fictional Dromaeosaur species (with scaly skins, no feathers, having pronated hands, snake-like eyes, chimpanzee-level intelligence, etc), which are incorrectly called Velociraptors (despite real Velociraptors being wolf/turkey-sized, being covered in feathers, having NO pronated hands, being much less aggressive, and having the intelligence like either a fox or a rabbit), would be one of the major threats to humanity and would breed and outcompete our native real life bears, big cats, and canines of various species.

Dragons would be a threat to humanity, unless they came from the How to Train your Dragon franchise and/or The Last Dragon documentary from Animal Planet, with various species of dragons threatening some endangered species to extinction, causing massive forest fires, etc. However, various Dragon species coming from the How to Train your Dragon franchise would become popular pets due to being dragons, and lots of people are big fans of dragons, however, most dragons from that series are too big to keep as pets, so they need to be breed to be much smaller to fit in house and be trained to be non-aggressive. Other than that, dragons would also be pests of livestock, would also burn down some houses made of wood.

A few of you know exactly who I'm thinking about.

Dragons are epic.

This reptile would kill off lots of endangered species as it somehow hunts for sports and no large land animal is big enough to repel Indominus Rex attacks.

Just like Indominus Rex, Indoraptor is one of another threats that could kill off most of humanity and would probably also hunt for sports. They would also kill off some native large land animals to extinction.

LOL, this may just as bad as Alastor, possibly even worse, since he's a demon, and he even threaten to destroy the world many times, just to have him wanting to marry Arle.

These half-zombie half-vampire undead species would be deadly to humanity as they would often kill livestock and even humans themselves for their blood. In some cases, Jiangshis are said to turn their human victims into Jiangshis if they bit them.

I didn't knew about this thing before

I know, right? He would definitely ruin our world if he existed, along with all other demons from the cartoon he came from.

How and why would Mickey Mouse destroy the world? He makes a lot of better choices than bad choices. He is also very popular.

This guy would have turned all the animals into robots! That would not have been good for the environment at all.