He is the father of Akira and Hikaru Akatsuki. He, along with Tony Stark, created the D.I.S.K. to contain super villains. However, Loki interfered and abducted Dr. Akatsuki and trapped the heroes in the D.I.S.K. When Akira and the Avengers went to Jotunheim to defeat Loki and rescue Dr. Akatsuki, he sacrifices himself to stop Loki. But in truth, he and Loki where taken to another dimension. Loki brainwashes Dr. Akatsuki into becoming Ronin in order to serve him. It is revealed that Dr. Akatsuki's true self still lies within Ronin.
- Ronin is an alias used by multiple characters in the Marvel Comics. Four characters who have used it are Maya Lopez (Echo), Clint Barton (Hawkeye), Alexei Shostakov (Red Guardian), and Eric Brooks (Blade). This version is exclusive to Marvel Disk Wars as Dr. Akatsuki was created specifically for the show.
- Avengers 4 will use the Clint Barton version of Ronin.
- In original Japanese airing, he is voiced by Hideyuki Hori, who is known voicing Ryu Hayabusa from Tecmo Koei's famed Ninja Gaiden/Dead or Alive.