Acid Ace (アシッド・エース) is the EM Wave Change form of Arthur C. Eos and his Wizard, Acid, in the Mega Man Star Force series. Using the Ace Program, they are able to Wave Change to form Acid Ace, and are registered under Project TC as No. 001.

Acid Ace is the first EM Wave Change form achieved via an artificial Wizard rather than an organic one, but a side-effect of this is that Ace's physical body is damaged over time. In addition, when Acid becomes corrupted with Noise, Acid Ace is capable of Finalizing into a berserk form called Acid Ace B (アシッドエースブラック Acid Ace Black).


Acid Ace is a highly customized and advanced EM Wave Change, designed specifically for light and mobile combat with the newest information analysis technologies.

Height: 186 cm
Weight: 73 kg

  • Anti-Ballistic Shield (アンチバリスティックシールド): This shield is designed to protect Acid Ace's head from attacks from either side. Furthermore, it can automatically defend against any attack for which there is already pre-existing analyzer data.
  • Wing Vernier (ウィングバーニア): A vernier that ejects high-density EM Wave Energy, enabling high speed movements that allow Acid to close the distance between him and his enemies for close-quarter combat. Also, because the energy is ejected at very high pressures, it works as a sharp sword that slices anyone it touches.
  • Acid-Wave Analyzer (アシッドウェープアナライザー): This part comprises the whole of Acid's capabilities for information collection and analysis. It uses every piece of information before it to create an unstoppable strategy. Through Acid, it can also connect to the Satella Police database and instantly delete any virus that has been registered there.
  • Satella Police Insignia (サテラボリス・エンプレム): The emblem of the Satella Police. All the Satella Police staff are required to display this symbol, which indicates that they are EM Wave crime prevention specialists.
  • Acid Blaster (アシッドブラスター): An EM Wave Energy gun featuring a Hunter-VG, this weapon enables Acid to dispatch a wide variety of attacks using the same Battle Cards as Mega Man. It was originally designed with long-range attacks in mind, but Acid Ace has proven himself to be more proficient with Sword-type cards.

Power and abilities

Acid Ace is fought three times in the story - once where he cannot be damaged and the player must survive a few turns, a second time normally, and third when corrupted as Acid Ace B. Two other forms also exist, Acid Ace R and BB (ダブルブラック Double Black) [2] which are fought in the Black Hole Server and as a random Nintendo Wi-Fi opponent, respectively.

Acid Ace is a unique boss, being able to use different Battle Card attacks in succession, in addition to his own attacks. Due to the nature of his various attacks, he is capable of attacking the weakness of all elemental Noise Changes.

  • Lock-On Sword: (ロックオンソード) Acid Ace locks onto the player's current position, then moves to that panel and slashes it, cracking the panel. This attack cannot be blocked, and later versions have him slash two times. Sword and Break attributes.
  • Acid Blaster: (アシッドブラスター) Other than normal shooting device, Acid Ace use this to dispatch a variety of Battle Cards below:
    • Mad Vulcan: (マッドバルカン) Fires eight shots at the player.
    • Buzz Saw: (ギザホイール) A buzzsaw travels down the column before curving at the player's row. It can be deflected by attacking the wheel and blocking it. Sword attribute.
    • Grand Wave: (グランドウェーブ) A wave travels across the ground and changes rows to move towards the player.
    • Dance Fire: (ダバフレイム) A flame hits all panels down the current column. Fire element.
    • Wide Wave: (ワイドウェーブ) Fires a wave that travels down three adjacent columns. Water element.
    • Stealth Laser: (ステルスレーザー) Fires three invisibility-piercing shots down the column. Elec element.
    • Squall: (コガラシ) A small tornado hits eight times on one panel, removing Barriers and Auras. Wood element, Wind attribute.
  • Wing Blade: (ウィングブレード) Acid Ace charges down his current column, hitting anything in his path as well as the adjacent columns. This attack can be blocked if the player is not directly in front of him. Wind and Break attributes.
  • Omega Laser: (オメガレーザー) Acid Ace charges energy and fires a multi-hit laser down his column as well as the adjacent column(s).

Battle Cards

Acid Ace (アシッドエース) Battle Cards are obtained by defeating Acid Ace.

Wing Blade (ウィングブレード) is a Giga Card exclusive to Mega Man Star Force 3 Black Ace.

Acid Arrest, known as Acid Illegal (アシッドイリーガル) in Japan, is the Battle Card of Acid Ace on his out of control form. When used, Acid Ace appears and uses three random attacks, which include Acid Blaster, Dance Fire, Wide Wave, and Squall. Acid Arrest is a promotional Battle Card, being only available during 2008 events in Japan or with the DS Download Service in North America.[3]

ID Battle Card Description Attack Element
Mega Class Card 19
SF3 BC M019.png
AcidAce Slash 1 emy w/lock-on sword 140 BC Element Null.pngBC Attribute Sword.pngBC Attribute Break.png
Mega Class Card 20
SF3 BC M020.png
AcidAceV2 Slash 1 emy w/lock-on sword 170 BC Element Null.pngBC Attribute Sword.pngBC Attribute Break.png
Mega Class Card 21
SF3 BC M021.png
AcidAceV3 Slash 1 emy w/lock-on sword 220 BC Element Null.pngBC Attribute Sword.pngBC Attribute Break.png
- (Mega Class Illegal Card)
Xxx acid aceX.png
AcidAceX Slash 1 emy w/lock-on sword 280 BC Element Null.pngBC Attribute Sword.pngBC Attribute Break.png
Giga Class Card 001 BC Giga WingBlade.png WingBlade 3-pnl wide fwd center break attack 450 BC Element Null.pngBC Attribute Break.pngBC Attribute Wind.png
- (Mega Class)
BC Mega AcidArrest.png
AcidArrest 3 rdm shots frm out-of-ctrl Acid - BC Element Null.png


The name Acid Ace holds the same possible references as the names of the wizard and human that make him, which are Acid and Arthur C. Eos, respectively.

Another possible reference drawn from Ace is the term flying ace, which is used to refer to military aviators who have succeeded in shooting down several enemy aircrafts, which is in direct relation to Acid Ace's shooting and semi-flight capabilities.



  • According to the official website, Acid Ace's profile data hidden within the Satellite Server was hacked by outside forces (presumably Dealer), which prompted an additional layer of security.
  • The profile section of Acid Ace's first page is misspelled as "Adic Ace".