Sometimes referred to as Artificial Humans, Nomu are powerful monsters created when humans have their bodies altered in order to hold multiple Quirks from All For One. The aforementioned human experiment ceases all brain function and requires commands from a superior in order for them to act.
It is currently unknown how exactly Nomu are produced. Doctor Ujiko and All For One possess several different laboratories that house these creatures.
Nomu is defeated by All Might and arrested by the Police Force. Naomasa Tsukauchi and his colleagues investigate Nomu and analyze his DNA. They discover he was originally just a small-time thug that had his body modified to hold multiple Quirks. This helps Detective Tsukauchi connect the Nomu to All For One himself.
Tomura Shigaraki and Kurogiri try to enlist the Hero Killer: Stain into their ranks. Their meeting gets hostile and Stain returns to Hosu City. Angry, Tomura requests the power to destroy the Hero Killer from his master. All For One tells Tomura that six new Nomu are in development but he can only use three. 
The trio of Nomu wreak havoc on the city and easily overpower Masaki Mizushima and his fellow Pro Heroes. The white Nomu crashes into a bullet train during a fight. Gran Torino leaps into action and tackles it back into the street. The Nomu attacks indiscriminately at civilians, but Endeavor arrives to stop it.
The white Nomu sends Endeavor's Hellflame back using an Absorption and Release Quirk. It follows up with a Muscle Augmenting Quirk and a Tongue Web combination, forcing Gran Torino to strike down the monster with a powerful Jet force dropkick.
Endeavor's sidekicks restrain that Nomu while their leader goes to deal with the rest. The winged Nomu and the black Nomu prove to completely outclass an entire group of Pros. Endeavor rushes in at the last moment to save their lives. Hellflame manages to completely cauterize the black Nomu's head, destroying it beyond Super Regeneration's ability to repair it. 
The winged Nomu flees the battle and Endeavor pursues it through the city. The No. 2 Hero manages to injure the Winged Nomu and save its hostage. In the aftermath of the U.A. Students battle with Stain, the Winged Nomu tries to secure another hostage. It grabs Izuku Midoriya and tries to fly away, but Stain acts quickly and kills the Nomu after paralyzing it with his Quirk.
Stain's influence draws new recruits to the League of Villains. Nine new villains and the chainsaw Nomu form the Vanguard Action Squad. They are sent to The Beast's Forest to invade the U.A. training camp and capture Katsuki Bakugo.
The chainsaw Nomu under Dabi's control. Twice reminds Dabi to sick the monster on the students. The Nomu brutally attacks Ragdoll, Momo Yaoyorozu, and Yosetsu Awase. Before it kills any of them, the mission is completed and Twice reminds Dabi to order it to return.
In order to rescue Katsuki, U.A. Students: Izuku, Momo, Shoto Todoroki, Tenya Iida, and Eijiro Kirishima track down one of the League's hideouts. They come across a Nomu production factory that house several different Nomu.
The Nomu Factory is raided by the Hideout Raid Team and all the different Nomu are restrained. All For One makes a rare appearance and attacks the Pro Heroes. He warps the Nomu to the other hideout to free Tomura and the other villains.
The Nomu attack the Hideout Raid Team's other squad and keep them busy while All For One warps the villains back to the Nomu Factory. These mid-level Nomu are eventually bested by Endeavor, Edgeshot, Kamui Woods and the Police.
Following the Hero Billboard Chart JP, Hawks meets with Endeavor in Fukuoka to discuss the appearance of more Nomu when they're suddenly attacked by High-End. High-End is a slightly intelligent Nomu and the most powerful Nomu to appear by a wide margin.
High-End is able to overpower the No. 1 Hero and cause a disastrous scene in Fukuoka comparable to the destruction All For One caused in Kamino. High-End even has the ability to produce nine low-level Nomu from its body using a storage Quirk.
Endeavor and Hawks are eventually able to work together to completely incinerate High-End beyond regeneration. Dabi later reveals this was just a test of the new Nomu's capabilities. 
Prior to the Hero Billboard, Doctor Ujiko makes contact with the League of Villains. In his laboratory, Dabi notices 12 unique Nomu kept in stasis. The Doctor calls them High-End and commends Dabi's eye. Later, he enlists Dabi's help to test one of the High-End.
Powers and Abilities
Nomu possess multiple Quirks and are designed to serve as mindless fighters. According to Doctor Ujiko and All For One, there a few different grades of Nomu and their strengths vary.
Low-End Nomu serve as foot soldiers and can overpower minor Pro Heroes. These Nomu are light in color and possess a multitude of Quirks as well as enhanced physical strength.
- Known Quirks:
Mid-End Nomu can contend with the top Pro Heroes. These Nomu are generally black in color and possess the Super Regeneration Quirk and are even stronger than low-end Nomu.
- Known Quirks:
High-End Nomu are intelligent Nomu that completely outclass the other Nomu. They possess abilities that can even overpower the top Pro Heroes, including up to six different Quirks.
- Known Quirks:
List of Nomu
- Horikoshi has hinted that the Flying Nomu from the Hosu Incident may be Katsuki and Izuku's winged childhood friend, Tsubasa.