Destrochloridium

Destrochloridium (デストロクロリディウム, Desutorokuroridiumu) was a Tiger-level parasite Mysterious Being who has the ability control human by infiltrating their brain and making them as its host.

Appearance
Destrochloridium is small monster with spotted skin, large eyes and lips. The monster has two antennae in its head. Both his hands are round with no fingers, and can transform into drills.

Personality
Destrochloridium is a sadistic Mysterious Being who likes to kill Humans for fun, as shown when he shoots a Hero Association staff member before apologising for his lack of self-control. He also appears to have a desire to increase his power by stealing the body of an S-Class Hero.

Monster Association Arc
Destrochloridium first appear when he controls a Hero Association staff to deliver the message from Gyoro Gyoro to the Hero Association. During the negotiation, he deliberately shoots a member of the committee with a pistol and sadistically saying that he slips his hand.

After Gyoro Gyoro finishes the demand to the Hero Association to gather all top class heroes to rescue the hostages in the Monster Association Headquarters, he begins to consider slaughter the committee with the host body only for Superalloy Darkshine to throw his host body into the wall. He then escape the host body and tries to take over Darkshine's body only to see his drill attack to be useless against Darkshine's impenetrable body. He is then killed by Darkshine as the S-Class Hero squishes him with his hands.

Abilities and Powers
While only a Tiger-level Mysterious Being, Destrochloridium can pose an enormous threat on his own due to both his small size and unique ability, as if he takes control of a strong enough body, then he can become more powerful than most other monsters.

Supernatural Abilities
Parasitic Mind Control: Destrochloridium can infiltrate a human's brain and control them as its host. It is shown that the controlled human often has Destrochloridium's antenna piercing through the head. A requirement for this ability is that, unlike Do-S, who can control multiple people just by striking them with her whip, Destrochloridium needs to enter his victim's body and manually control them.

Physical Abilities
Drill Arms: Destrochloridium has drills for arms that he can use to attack an opponent as well as the mean to infiltrate human's body to control it. The parasite notes that its drills are as tough as steel.

Enhanced Speed: He possesses great speed due to his miniature size, as no one noticed him exiting the body of the Hero Association staff member he was in after Superalloy Darkshine threw him into the wall. He was even able to appear beneath Darkshine before any else noticed his presence and proceeded to attack the hero in an attempt to take control of his body before anyone could stop him.

Trivia

 * "Destrochloridium" is a play on the word "destroy" and Leucochloridium, which is a type of parasitic worm.