The King

9:00 - Kingslayer started thrashing around with its host in its cell. It shouted, "He's coming, oh, he's coming", time and time again, excited.
9:10 - When the damage to its cell became severe, Kingslayer was let out. It immediately started running towards the exit. All of the guards were instructed to not try to stop it.
9:20 - Kingslayer reached the surface and started looking around at the sky before focusing at one point.
9:37 - A giant castle showed up above the city.
9:40 - A black substance started to rain down from the castle. Whatever it touched, turned into intense growth, mostly that resembling thorny brambles.

The King is a sapient and sentient anthropomorphic Wrong. He possesses powers that let him modify the landscape and mutate and control living beings. His castle is considered a part of him and travels wherever he goes.

Appearance

The King is a 4-meter tall humanoid whose body looks like it's made out of a mix of sticks, vines, antlers, and insect carapaces. His proportions seem to be a little elongated when compared to those of humans, mainly due to his very slim torso. He possesses an additional pair of arms, growing just underneath his first one. There are webbings between each upper and lower arm, which don't limit their independent moves in any way.
His whole neck and lower part of his face, up to the tip of the nose, are covered with a bark-like growth. It's unknown whether there is any mouth underneath it. Just above the growth, there's a pair of main eyes, similar in structure to those of humans. Both his sclera and irises are of intense purple color, visible even in the dark. Each of his eyes is surrounded by six simple eyes looking like purple dots, with two of them on each side of the eye and above it. Both King's eyebrows and his hair are made out of structures resembling insect wings.
King spends all of his time sitting on his throne. When resting, his head hangs low, his eyes closed, he breathes slowly. When he tries to reclaim his kingdom, his hands cover his face, while the black sludge drips down off his face

Powers

Restoring what was lost

When The King arrives at the new dimension, he tries to turn it into his first kingdom. While sitting on his throne, a black liquid starts to seep out of his face. It travels through the castle through channels and pipes, lower and farther. It starts to rain down on the ground below. Whatever the liquid touches, transforms into part of The King's world. Endless thickets of thorny brambles, megaflora, plants never seen before. Even the landscape changes its shape, forming new formations. With each passing day, The King is alive, the affected territory doubles its size. Additionally, the black liquid doesn't affect the areas it already transformed.
The King can't produce the black liquid constantly. For every 4 hours of creating it, he needs at least two hours of rest. 2 hours when it is safe to try to get through the border formed by the area that will be affected in the next flooding.

Loyal subjects

But the flora and the landscape are not the only things affected by the black liquid. Any living being that touches it will be transformed into the counterpart of its species from The King's world. Those counterparts are usually more intelligent, vicious, and mischievous. Even the animals that would normally steer away from humans will probably want to make a "little prank" on them. The severity of those "pranks" can vary between something that will leave big, painful bruises and something outright lethal.
Even the slightest touch of the black liquid can infect a person, though they may not notice that something is wrong with them. The smaller the area of contact, the slower their transformation will be. All of the affected creatures are completely loyal to The King and will work against anyone who tries to kill him. While in his presence, they are completely under his control.

Off with their heads

By merely moving his finger from side to side, The King can cut stuff up to 10 meters away from him. He uses that ability only when something disturbs his peace by trying to wound him for too long or when the Kingslayer and its bearer move within a meter or two from him.

Current status:
Not yet present. It's unknown when the Wrong will show up and if the words of the Kingslayer are true. If they are, at some point The King will show up.

Indestructible

Both The King and his castle can't be damaged by any known weapons, even other Wrongs or Weirds. The only way to kill The King is to deal damage to him with the Kingslayer.

Castle in the sky

A big, floating structure made out of dark green, wood-like, and stone-like materials. The castle is a square building, 1km wide and long. From the outside, it resembles a mixture of gord and very old castles. Most of the walls are covered with moss, ivy, or spiky vines. Inside, it's a tangled mess of rooms with unknown purpose and a literal maze of corridors. Many of them have grooves in the floor, through which a black sludge is transported.
In the middle of the castle, there's a throne room, where The King spends all of his time.
From the bottom of the castle, from various parts of it, a black sludge spills out, flooding the lands below it.

Dimension jumping

When The King dies, his body and his castle disappear from the dimension they are currently in. All the changes caused by King's powers revert, restoring the world to what it was before his arrival.