"Stay out of my way, you useless piece of trash."

―Ace Killer to one of his men, after killing him.
Ace Killer
Ace K Manga Profile
Height: Human Like
Weight: Human Like
Home world: Unknown
First appearance: TBA
Latest appearance: TBA
Actor/Voice actor: None
Suit actor: None
Status: Alive
Affiliation: Ace Killer Squad (Leader)
Roar(s): None

The leader and namesake of the Ace Killer Squad.


Ace Killer is a rather relaxed fellow, despite the bloody work he does. He seems to be always calm and collected and making light of the situation, whether it is torturing someone or simply making light of a grim situation. Even in the face of certain death and after being enraged, Ace Killer can still find it in himself to crack a quip.

He also seems to have a serious lack of concern for sentient life. This is especially true when he becomes angry and will kill even his men if they get between him and the object of his anger.


Ace Killer was in fact the being who caused the crash of the plane carrying Seiji's family and an Inspection Party from the Star Cluster Alliance. Yapool was a member of said Inspection Party and saved Seiji, the only human survivor, although he refused to tell the true version of the crash. When Seiji confronted Yapool with a photo of Ace Killer's blade, the alien admitted that Ace Killer was the assassin but not the mastermind.

The mercenary was later seen accepting a job from an unknown person to kill Ultraman. Soon afterwards Shinjiro and Moroboshi responded to a report containing evidence of alien activity. When they arrived, Moroboshi told his companion to wait outside while he investigated the building. Inside, he encountered the Ace Killer Squad, and the building was destroyed a massive fireball.

From the blaze emerged Ace Killer, Alien Woovelve, Alien Nepenthes and the rest of his goons, who were surprised by the appearance of Shinjiro as well. One of the squad informed Ace Killer that Moroboshi was not their target, prompting him to attempt to eliminate Shinjiro to cover it up. However, Seiji also arrived, their true target.

A large battle erupted between the aliens and Ultramen, made even more chaotic with the timely arrival of Jack and Red. Even then, the Ace Killer Squad was dominating until Shin Hayata arrived in the prototype Ultraman suit. As Red fought with Woovelve and Shinjiro took on Nepenthes, Ace Killer chased down Seiji.

Ace Killer managed to literally disarm Seiji, severing one of his prosthetics. The two began to argue before Ace Killer fulfilled his name, but he also lost an arm when Seiji recovered. Seiji stood and prepared to fight the alien, declaring that he was an Ultraman and that he planned to mow Ace Killer down. Seiji used a weapon of his own to remove Ace Killer's arm in turn, enraging the assassin and causing him to slay one of his own men.

Choosing to kill him personally, Ace Killer dashed back and forth, slashing Seiji until plunging his hatchet into his chest. This proved to be his undoing as the boy grabbed him and pinned him down, removing his hand to turn his arm into a Specium Cannon. Ace Killer resigned himself to his fate, and Seiji vaporized his head with a blast to the face.

Powers and Abilities

  • Superhuman Body: Whether it is his armor, natural body or a combination of both, Ace Killer can keep up with the SSSP's Ultramen.
    • Speed: Ace Killer is shown to be able to move at incredible speeds in a short distance and have excellent reflexes. He is able to perform a dash, wherein, to most human eyes it practically appears that he is teleporting.
  • Gun: He possess a gun that fires 'Dagalette shells that can pierce the Ultraman Armor. Though it cannot pierce his flesh (possibly due to his Ultraman Factor, the suit's under armor, or a combination of both), it can still cause Shinjiro great harm.
    • Marksmanship: He has excellent reflexes and aim with his gun.
  • Hatchet: He owns a short, two pronged blade which he is incredibly fond of using.
  • Mimicry System: Instead of switching out of his gear, he uses a Mimicry System to appear human.


  • Ace Killer's blade weapon is inspired by the original's battle sai.
  • Ace Killer was part of the operation dealing with the barcoded bodies, as the base which was destroyed as part of his trap was his 'meat processing job'. It is also heavily implied that the hatchet he used in battle was a literal 'meat hatchet'.
    • Said corpses were stated to be sold to aliens who like eating humans.

ULTRAMAN Manga Characters
Ultraman Factor Shinjiro Hayata | Shin Hayata
Ultramen Ultraman | Shin Hayata | Shinjiro Hayata | Dan Moroboshi | Seiji Hokuto | Kotaro
SSSP Dan Moroboshi | Mitsuhiro Ide | Ed | Akiko Fuji

Secondary Characters Endo | Kurata | Rena Sayama | Jack | Pigmon's Friends | Seiji Hokuto | Kotaro | Ultraman | Dave

Star Cluster Alliance Ed | Mephisto Ambassador | Adad | Alien Awazo
Aliens Bemular | Ed | Alien Adacic | Alien Igaru | Red | Alien Kadder | Alien Bris | Adad | Yapool | Mephisto Ambassador | Biological Weapons | Yuko Minami | Ace Killer Squad | Alien Awazo | Alien Pedan | Alien Druz
Ace Killer Squad Ace Killer | Alien Nepenthes | Alien Woovelve
Star of Darkness Alien Pedan | Alien Druz