Dr. Maddiman

is a Boss Yo-kai.

The Yo-kai Medallium bio reads; "This madman used to perform experiments on humans at his hospital. Now, as a Yo-kai, he continues his search for new test subjects."

Moteamasu
Before he became a Yo-kai, Dr. Maddiman started doing research to try and create the Ultimate Yo-kai Amaterasu. In Yo-kai Watch 2, his creation is finally completed, but he renames it to "Moteamasu" as it turned out much different than he thought it would.

After Moteamasu is defeated by the player, Dr. Maddiman expresses great sorrow, and later battles the player to try and avenge it.

Katie Forester/Nate Adams
In Yo-kai Watch, Dr. Maddiman doesn't seem to think highly of the player, expressing disbelief at the fact that a child like them could defeat him.

In Yo-kai Watch 2 he resents them for defeating Moteamasu, but comes to be grateful for how they helped him.

Inaho Misora & USApyon
He befriends them in Yo-kai Watch 3

Abilities and Powers
He has the ability to "take a Yo-kai's heart", causing them to become strange and attack allies.

His "Soul Absorb" move can empty out a Yo-kai's Soul Meter, preventing them from using their Soultimate.

He can use the move "Blood Refill" which heals him. When he is charging it up, pin the beating hearts in the background to pop them and cancel the move.

History
In Yo-kai Watch, Dr. Maddiman appears as the Boss Yo-kai of Chapter 10.

After the player learns from Draggie that there is a bad Yo-kai at Nocturne Hospital, they decide to investigate. There they're put through several health checks until finally meeting the hospital director, who appears to be a friendly human. However, after seperating the player from Whisper, the director reveals himself to be Dr. Maddiman, who then attempts to kill the player and a boss battle ensues.

Upon being defeated, Dr. Maddiman calls out to his master, Chairman McKraken, giving the player the first hint of who is behind all the bad things that happened during the events of the game.

In Yo-kai Watch 2, Dr. Maddiman appears as an optional Boss Yo-kai.

During a request at Nocturne Hospital, the player will stumble upon Dr. Maddiman's secret undergound laboratory and interrupt him during the completion of his creation Moteamasu. Out of curiosity, Whisper will release the unstable artificial Yo-kai, despite Dr. Maddiman's protests. Afraid of what might happen, Dr. Maddiman retreats.

Later he can be found in the hospital's surgery room, lamenting the defeat of Moteamasu. It's at this point that he tries to recall why he began his research in the first place, but fails to do so. Feeling pity for him, the player decides to help him by collecting the scattered pages of his old diary. Upon reading these pages, Dr. Maddiman remembers his life as a human, and the reason for why he started doing his research, and thanks the player. However, he still attacks them, out of a desire to take revenge for Moteamasu.

Despite this, after being defeated again, he is actually very happy. Since he now remembers his life, he is determined to start his research all over again, only this time he says he will succeed and take over the world for sure. He then tells the player that he wishes to meet them again one day and disappears.

In Yo-kai Watch 3, Dr. Maddiman returns as a Boss Yo-kai of Inaho's Chapter 5.

He will request Inaho's and USApyon's detective agency to help him with an experiment of his, which turns out to be him desperately needing a can of Dr. Rapper to help him calm down before experimenting. After receiving a can of the aforementioned beverage from Inaho, he will ask the two to help him with something else, too. It happens that the three Experimental Animal Yo-kai he was going to use have all have escaped from his laboratory, and he needs Inaho and USApyon to find them for him.

Once Inaho brings the Experimental Animal Yo-kai to him, he reveals that he plans to combine them into a "Remodeled Yo-kai", causing Inaho and USApyon to distrust him. USApyon, having been an experimental animal himself, gets especially angry at Dr. Maddiman, and their argument results in a boss battle.

Afterwards USApyon tells Dr. Maddiman about his past, and that Dr. Hughley would have never made him do something he wouldn't want to. Dr. Maddiman brought to tears by this, and apologized to the Experimantal Animal Yo-kai for what he was about to do. He decides to release them into the wild, and asks Inaho and USApyon to take him to sea, so that he can do so.

Later in the chapter, his Experimental Animal Yo-kai are combined into Gamegosu, and he asks Inaho and USApyon to stop it and save his friends.

In a later chaper, Inaho has to get Steve Jaws' Hammerheadhand that he borrowed from him.

Name Origin
"Maddiman" comes from "madman. "Yaburekabure Inchō" comes from "yaburekabure" meaning "desperation".