Mycroft is a very tall and largely-muscled man.
Although Mycroft is one of the first masters to appear in the HSDK series, his personality remains mysterious. However in both the original series and HSDK, Mycroft has expressed joy in fighting powerful opponents with his bare hands. In the original series, he made a public statement murdering someone with his bare hands in order to get the attention of Sakaki and in HSDK he was overjoyed at the fact that he is able to use his techniques against a weapon master.
Overall he seems to have great pride in his skills as an unarmed fighter. He also shares some traits with the One Shadow Nine Fists and Ryōzanpaku masters in terms of avoiding or preventing other masters from attacking disciples. In the original series, he only attacked Kenichi, because Kenichi shot at him first while in HSDK he decided to save Kenichi from Mihai Știrbey even though he was under no obligation to do so.
He is also very fond of smoking his pipe.
Mycroft worked with Christopher and Sakaki and did a variety of work in the USA. They protected high-ranking officials and even worked for the FBI. However, while Mycroft and Christopher enjoyed doing whatever job they could take, Sakaki refused to partake of missions that brought harm to children and the elderly, and the poor. Annoyed with this, Mycroft and Christopher had planned to kill Sakaki but instead both of them were buried in the desert by Sakaki (Kenichi envisioned the Karate master doing this with a bulldozer). While Christopher survived and became a member of Yami and Sakaki eventually joined Ryōzanpaku, Mycroft has become a member of Yami along with Christopher.
- Master Chinese Hybrid Martial Artist: Mycroft is a master of Chinese Kenpo. Mycroft uses a special palm based style of Chinese kenpo that can cause serious damage to the opponent at close distance, as long as he is touching a part of his opponents body, he can flow his power directly into that part, which makes him a dangerous up-close fighter. Unlike most Chinese Kenpo practitioners, Mycroft's style of fighting is a little bit more unique. According to Mycroft, When Hong Kong was still under British rule, his family learned and stole secrets from Chinese Kenpo, and used what they learned to create a more evolved, more brutal British variation of normal Chinese Kenpo, which would technically make Mycroft's style of Chinese Kenpo a type of Hybrid Martial Art. Kenichi even speculated that Mycroft can possibly match his own master, Kensei Ma, in the art of Chinese Kenpo.
- Enhanced Strength: As a master-class fighter, Mycroft has proven himself to have a massive amount of strength. During his battle with Mihai Știrbey, He was able to deal a critical blow to him in one shot, and injure him to a serious degree. Miu stated that his attacks are like Nitroglycerin.
- Enhanced Speed: He was shown to be fast enough to rescue Kenichi from getting his head cut off by Mihai Știrbey.
Mycroft make a reappearance during Yami's plan to begin the Eternal Setting Sun, as both him and Christopher Eclair shown up and interrupt Mihai Știrbey's attempt to kill Kenichi and Miu . When Kenichi asks who he is, Mycroft introduces himself. After receiving payment from Shigure, Mycroft and Christopher engage the weapons users as Christopher fights Seitaro and Mycroft fights Știrbey. Mycroft begins fighting with Mihai Știrbey and is able to land a hit on him, much to Știrbey's surprise. Mycroft explains that his fighting style is an evolution of Chinese kenpo, allowing him to transfer his power against an opponent as long as he makes contact. Știrbey comments that the techniques of the unarmed division are scary, and Mycroft says that same about Știrbey and his scythe. Mycroft says that Știrbey's big weapon will not hit him but suddenly gets cut on his arm. Știrbey comments that his scythe was made by Shugure's father and that it should not be underestimated as it "bends and flows like a willow".
Once Shigure used her Sōto Kyōrenzan, she tells Christopher and Mycroft to take her disciples away, to which they do as Mycroft stops the Hachiou Knight with his thrust. They manage to escape as Mycroft lights his pipe and watches solemnly as Shigure is defeated by the Hachiō Executioner Blade members. He later returns to England as Christopher stays behind for the time being.
- vs Shio Sakaki (Loss)
- vs Mihai Știrbey (Undecided)
- Mycroft first appeared in the original Kenichi series as an old partner and now enemy of Sakaki. He clearly wants to kill/defeat Sakaki, but disapproves of his female assistant's attempt to shoot Sakaki, wanting to defeat his archenemy with his own hands. He uses a palm based kung fu style.
- He was the very first antagonist master to appear in the original series while in HSDK, it was Sōgetsu Ma.
- In HSDK's predecessor, Tatakae! Ryōzanpaku Shijō Saikyō no Deshi, he had an inverted cross tattooed on the back of his hand.