Overgrown Rover

The Overgrown Rover is a major antagonist from the One Punch Man series. It is a massive, dog-like creature that serves as one of the high ranking members of the Monster Association, serving as the guardian to seek out intruders. After the fall of the Monster Association's defeat, it and Black Sperm were later taken in care by Butterfly DX, Chain'n'Toad and Forte.

Appearance
Overgrown Rover has a massive dog-like appearance, standing on its four hinds. It has a pair of three, bright eyeballs and a set of sharp teeth that sticks out of its skull. It overall has a demonic appearance with its fur rising in a sharpened appearance.

It was originally a huge creature, but after its defeat by the Hero Association, its size drastically reduced to a normal-sized dog.

Personality
Overgrown Rover behaves nearly identical to an obedient dog. It carries out orders without hesitation and pledges its loyalty to whomever. Despite its ferocious appearance, it is generally a calm monster that observes its surroundings. However, once it's been provoked, it can easily lash out in anger and attack like a savage beast without warning.

Monster Association Arc
Overgrown Rover coincidentally encounters Garou and Busaiku in the hideout, whom were attempting to escape. Despite spotting them, Rover did nothing and simply observed them as the two quietly walked away.

Eventually, Garou and Busaiku managed to get away, but are then confronted by Super Mouse, Showerhead and Unihorn. During the battle, Unihorn launches his horn straight towards Garou. Garou managed to avoid it, but the horn headed straight to Rover, stabbing it, causing Rover to roar loudly. After killing the three monsters, Rover confronts Garou himself.

Garou engages Rover in a fierce battle. Rover blasts him through the floors of the hideout, destroying the majority of the place in the process. Despite taking such damage, Garou was still standing. Rover continues to fire its blasts at him. Garou, however, was able to evade him and land a striking blow on Rover. Despite using such force, however, Rover tanked the hit as if it was nothing and sent him flying back down through the floors once more, bringing him down to Gyoro Gyoro.

Rover later encounters Saitama and attempts to battle him, only to be beaten into submission. Rover is then confronted by Fubuki, Genos, Bang and Bomb, who all try their best to defeat Rover. Despite their best effort, Rover remained standing, shrugging off their attacks. Frustrated at this point, Bang had wished that Rover would just simply remain still and quiet, only for Rover to suddenly take command and remain seated.

Psycho Sisters Arc
Eventually, Rover's size drastically reduced to that of a small dog. After the fall of the Monster Association, Rover met up with Black Sperm, who was now standing at one cell left. With nothing left to do, the two decided to tag along with Saitama and followed him to the Hero Association. They are then placed in the hands of three heroes.

Powers and Abilities
Overgrown Rover is one of the most powerful members of the Monster Association, as it is estimated be a Dragon Level Threat; monsters that are capable of destroying multiple cities. Because of this, it is often placed next to monsters such as Black Sperm, Evil Natural Water and Elder Centipede.

Rover has a variety of powers and abilities that overall makes it a deadly monster. These include;
 * Immense Strength: Rover is incredibly strong enough to break through solid concrete and stone with ease. He has also shown to break Unihorn's horn, which was said to be in a near-unbreakable state.
 * Immense Speed: Rover can move at insane speed and has shown to outrun those like Garou, who can move very fast as well. His overall speed rivals with the top S-Class heroes.
 * Immense Durability: Rover can tank serious hits with almost little to no damage. It has shown to survive attacks from powerful beings such as Garou and even Saitama himself, who is known for one shotting monsters with no effort. Because of its insane bulk, Bang and Bomb had to rely on using Cross Fang Dragon Slayer Fist, a technique that's more powerful than the one used on Elder Centipede.
 * 026-027.pngEnergy Project: Rover can fire blasts made of energy from its mouth. These energy blasts are powerful enough to create shockwaves to cause an entire city to shake and rumble, as well as burn through stone to ashes and one shotting Demon Level Threats.