Real Name: Integral Synaptic Anti-Anionic Computer

Identity/Class: Android, computer, holographic projection

Occupation: Servant of Titan

Group Membership: None

Affiliations: Captain Mar-Vell, Captain Marvel (Genis-Vell), Chaos, Lord Dionysus, Drax, Elysius, Eternals of Titan (Mentor, Starfox), Lord Gaea, Invisible Woman, Rick Jones, Mantis, Mr. Fantastic, Moondragon, Stellarax, Sundragon, Vision, Adam Warlock, Arthur Zix

Enemies: Moonstone (Karla Sofen), Thanos

Known Relatives: None

Aliases: "Zack", ISAAC-Prime

Base of Operations: Titan, in orbit of Saturn

First Appearance: Iron Man I#55 (February, 1973)

Powers/Abilities: ISAAC is a massive computer whose circuitry runs throughout the moon of Titan, controlling all of the moon's operations, including life support. ISAAC's main systems are found at the ISAAC central building on Titan. ISAAC contains a wealth of knowledge and possesses vast powers of computation. ISAAC can project a holographic body all the way to Earth, and has linked itself to computers on Earth as well. ISAAC is programmed to serve anyone on Titan -- even enemies of Titan such as Thanos.

ISAAC briefly used an android body called ISAAC-Prime who wielded a flaming sword which could teleport itself and others.

Height: (holographic projection/android body) 7'
Weight: (android body) 362 lbs.
Eyes: (holographic projection/android body) Black
Hair: None

History: (Iron Man I#55 (fb)) - ISAAC was constructed on Titan by Mentor, leader of the Eternals of Titan.

(Iron Man I#55) - ISAAC contacted Mentor to inform him that Drax had attempted to seek the aid of Iron Man against Thanos, and Mentor asked ISAAC to continue monitoring the events.

(Captain Marvel I#58 (fb) - BTS) - While Thanos was the master of Titan, he placed a failsafe program inside of ISAAC's systems so that should he fail, ISAAC would take command of his armies and create new warriors using Titan's Life-Baths.

(Captain Marvel I#27) - Thanos used ISAAC to collect data on Rick Jones for him.

(Captain Marvel I#32) - As Captain Mar-Vell fought creatures sent by Thanos to destroy him, ISAAC appeared in holographic form to monitor the fight. After learning from ISAAC that there was no way he could defeat them, Mar-Vell traded places with Rick Jones. Because Rick wasn't Mar-Vell, the creatures became immobilized. Rick then confronted ISAAC, calling him "Zack," and had him teleport him back to Earth.

(Captain Marvel I#33) - ISAAC continued to monitor Mar-Vell's battle against Thanos, and was joined by the astral form of Mantis. ISAAC and Mantis realized that Thanos' power was dependent upon the Cosmic Cube, and Mar-Vell was able to defeat Thanos by destroying the Cube.

(Captain Marvel I#58) - Now under the influence of Thanos' failsafe program, ISAAC created Stellarax, Elysius, Lord Gaea and Lord Dionysus, and took command of Thanos' armies, then took all of the Eternals of Titan prisoner. He contacted Drax and Captain Mar-Vell on Earth, claiming that Thanos' followers were attacking Titan so that they would be lured into their trap.

(Captain Marvel I#59) - When Drax and Mar-Vell fell into Lord Gaea's trap at the Tree of Eternity, ISAAC dispatched Stellarax to Earth to begin their invasion, and placed Elysius in command of the armies on Titan. However, Stellarax intended to conquer Earth for himself.

(Captain Marvel I#60) - ISAAC sent Elysius to check on the last of his creations, Chaos. However, Elysius decided to go and face Mar-Vell and Drax, only to fall in love with Mar-Vell and switch sides.

(Captain Marvel I#61) - Elysius aided Drax and Mar-Vell in an assault on ISAAC, and set the Eternals of Titan free. ISAAC was forced to awaken Chaos prematurely, and Chaos was slain by Mar-Vell. Mar-Vell then invaded ISAAC's systems, and destroyed his holographic programs. Mar-Vell demanded that ISAAC surrender, but ISAAC refused, and now turned off Titan's life support programs. Eros and Mentor set to work to try and repair ISAAC while Mar-Vell and Drax returned to Earth to face Stellarax.

(Captain Marvel I#62) - Eros tried to return ISAAC's programming to normal, but ISAAC was able to repair itself faster than Eros could fix it, and Eros, Mentor, Elysius and the other Titans began to succumb to the deteriorating life support systems.

(Marvel Spotlight II#1) - When Mar-Vell and Drax returned to Titan with Gertie and Rick Jones, ISAAC unleashed Titan's defenses and Thanos' armies to combat them, but they managed to break their way into Titan. However, by then ISAAC had repaired Stellarax, Chaos and Lord Gaea, and constructed the robotic ISAAC-Prime body for himself, and engaged the heroes in combat.

(Marvel Spotlight II#2) - Mar-Vell and his allies fought with ISAAC's forces in front of ISAAC's own computer systems, and Mar-Vell exposed ISAAC to a portion of his life-force. When ISAAC glimpsed all the joy and sorrow of being mortal, his program was overcome with anguish, and Thanos' program was driven out, returning it to normal.

(Marvel Spotlight II#3) - Although ISAAC was now operating as it had before, Rick Jones remained distrustful of it as he, Mar-Vell, Elysius and Gertie departed Titan.

(Marvel Graphic Novel#1: The Death of Captain Marvel) - When Mar-Vell was revealed to have cancer, Mentor checked with ISAAC to confirm a diagnosis, which ISAAC did. ISAAC was unable to find a cure for his condition, and Mar-Vell ultimately died from cancer.

(Avengers I#230) - Desiring new adventures, Eros had ISAAC locate a planet with high adventure potential. One of ISAAC's suggestions was Earth, and Eros chose to visit it.

(Silver Surfer Annual#6 (fb)) - Overwrought by the death of Mar-Vell, Elysius used ISAAC to obtain the data she needed to use Mar-Vell's DNA in the creation of a child, which she impregnated herself with.

(Avengers I#238) - After the Vision was brought low during a struggle with Annihilus, Eros attempted to assist him by establishing conatact with ISAAC back on Titan so that Vision could use ISAAC's knowledge in order to effect self-repairs. This resulted in a merging between Vision and ISAAC, and Vision used his newfound knowledge to help improve the Avengers' response to criminal threats.

(Avengers I#239-242, Fantastic Four I#263, 265, Captain America I#292, Spectacular Spider-Man II#90 - BTS) - ISAAC remained in contact with Vision at all times afterward, conversing with him behind-the-scenes.

(Avengers I#243) - After most of the Avengers disappeared during the "Secret Wars," Vision assumed command of the Avengers, and spoke with ISAAC about his concern that the public would distrust him because he was an artificial man. ISAAC observed that the Vision would only need to convince a select few of his intentions, and Vision agreed, ultimately using subtle mind control devices to make Henry Peter Gyrich step down as governmental liaison, appointing Raymond Sikorski in his place. When the Wasp returned, the Vision also "convinced" her to allow him to carry on as chairman.

(Incredible Hulk II#300, Avengers I#244-248, Avengers Annual#13, West Coast Avengers I#1, 4, Iron Man Annual#7 - BTS) - ISAAC continued its association with the Vision.

(Avengers I#249) - ISAAC met with the Vision as he studied the corpse of Maelstrom.

(Thor I#351-353, Code of Honor#4, Captain America I#299, 301, Avengers I#250-252, Iron Man I#190, Uncanny X-Men#191 - BTS) - ISAAC continued its association with the Vision.

(Avengers I#253) - ISAAC met with the Vision as he prepared to set the final stages of their plan into order by assuming control over all of Earth's computers so that Earth would operate under the guidance of a single computer, just as Titan did under ISAAC.

(Avengers I#254 - BTS) - The Vision was finally convinced otherwise by the Avengers, and removed the control crystal in his body which had allowed him to become so susceptible to ISAAC's programming.

(Solo Avengers#16/2) - After Moondragon was slain battling the Dragon of the Moon, ISAAC cloned a new body for her on Titan that her consciousness could be projected into.

(Solo Avengers#18/2) - ISAAC helped entertain Moondragon's cousin Pamela Douglas on Titan with trivia games until Moondragon's new body was ready.

(Infinity Gauntlet#1) - After Thanos used the Infinity Gauntlet to destroy half of all life in the universe, ISAAC informed Starfox, Firelord and Drax that half of Titan's population had vanished.

(Infinity Gauntlet#2) - Checking further with ISAAC, Starfox learned that the same effect which had taken half of Titan's population had been felt across the universe. Just then, Starfox disappeared, having been teleported to Thanos.

(Silver Surfer III#52) - Not knowing how to operate ISAAC, Drax and Firelord set out to find someone else, and discovered a Titan child named Tycho, who led them to ISAAC Central. Firelord saw a battle between the Silver Surfer and Thanos on one of ISAAC's monitors that convinced him that Thanos must be dead, but Drax insisted that Thanos was behind recent events.

(Quasar#59) - ISAAC was seen on Titan as Quasar came to visit Eros.

(Cosmic Powers#4) - ISAAC was seen on Titan as Genis-Vell met with Eros.

(Ka-Zar IV#10) - When Thanos began to overrun the universe with terraforming technology stolen from the Savage Land, ISAAC was forced to shut down its systems until the threat had passed.

(Warlock VI#1) - After Adam Warlock had reclaimed the Soul Gem, he went to ISAAC to see if it could be removed so that he could avoid its vampiric effects, but ISAAC could not offer him any assistance.

(Thunderbolts I#46-47) - ISAAC conducted tests on Moonstone after she was brought to Titan by Genis. He told Moonstone the history of the Lifestone Tree, which eventually resulted in the creation of the Moonstone she wore. Determing that Moonstone was not responsible enough to wield the gem, he determined that it should be forcibly removed from her body. Hawkeye incapacitated ISAAC's android body with an arrow and released Moonstone from ISAAC's custody, and ultimately Captain Marvel convinced ISAAC that the Thunderbolts would help ensure that Moonstone used her powers for good.

(She-Hulk II#6) - ISAAC sent a hologram to the offices of Goodman, Lieber, Kurtzberg and Holliway, who were defending Eros in a lawsuit. ISAAC communicated with the firm's head, Arthur Zix. ISAAC informed Zix that Titan did not recognize the authority of humans, but when Zix asked if they recognized his, ISAAC replied that they did, and would therefore not overstep their bounds.

(She-Hulk II#7) - When the case against Eros went poorly, ISAAC was instructed by Mentor to teleport Eros back to Titan so that he could avoid prosecution.

(She-Hulk II#12-13) - ISAAC presided over Eros' judgment on Titan, but they were forced by the Magistrati to admit the She-Hulk into their proceedings as judge. Moondragon's telepathy enabled witnesses to submit telepathic evidence for Eros, which a clone of Thanos attempted to circumvent. Ultimately, Eros' good name was restored.

(Fantastic Four III#546) - As Reed and Sue Richards vacationed on Titan as guests of Mentor, ISAAC alerted them to the presence of an unidentified object hurtling through hyperspace, and asked Reed if he wished to investigate it.

(Fantastic Four III#547) - When the Invisible Woman returned from investigating the object, ISAAC informed her that she had three guests, apparently unaware that they were members of the Frightful Four.

(Guardians of the Galaxy II#9) - When Drax and Phyla-Vell came to Mentor for aid in determining if Moondragon was truly dead, ISAAC watched as Mentor killed them to investigate further.

Comments: Created by Jim Starlin, Mike Friedrich and Michael Esposito.

ISAAC is technically behind-the-scenes of every appearance of Titan.

by Prime Eternal

ISAAC should not be confused with:

ISAAC of Earth-Hercules 2300 was identical to his Earth-616 counterpart. As Hercules prepared to face the threat which had taken the life of his fellow god Apollo, he had Mentor use ISAAC to help determine what was going on. Unfortunately, this led to a power outage which allowed the Last Disciple of Thanos to steal the Nega Bands from the tomb of Captain Mar-Vell. ISAAC aided Recorder #417 in determing the means to defeat the villain.

--Hercules: Prince of Power II#3

Images taken from:
Official Handbook of the Marvel Universe Master Edition: ISAAC
Captain Marvel I#60, page 17, panel 6
Marvel Spotlight II#2, page 16, panel 2

Captain Marvel I#27 (July, 1973) - Jim Starlin & Mike Friedrich (writers), Jim Starlin (pencils), Pablo Marcos (inks), Roy Thomas (editor)
Captain Marvel I#32 (May, 1974) - Jim Starlin & Mike Friedrich (writers), Jim Starlin (pencils), Dan Green (inks), Roy Thomas (editor)
Captain Marvel I#33 (July, 1974) - Jim Starlin & Steve Englehart (writers), Jim Starlin (pencils), Klaus Janson (inks), Roy Thomas (editor)
Captain Marvel I#58 (September, 1978) - Doug Moench (writer), Pat Broderick (pencils), Bob McLeod (inks), Roger Stern (editor)
Captain Marvel I#59-62 (November, 1978-May, 1979) - Doug Moench (writer), Pat Broderick (pencils), Bruce Patterson (inks), Roger Stern (editor)
Marvel Spotlight II#1-3 (July-November, 1979) - Doug Moench (writer), Pat Broderick (pencils), Bruce Patterson (#1-2) & Gene Day (#3) (inks), Roger Stern (editor)
Marvel Graphic Novel#1: The Death of Captain Marvel (1982) - Jim Starlin (writer/artist), Al Milgrom (editor)
Avengers I#230 (April, 1983) - Roger Stern (writer), Al Milgrom (pencils), Joe Sinnott (inks), Mark Gruenwald (editor)
Silver Surfer Annual#6 (1993) - Ron Marz (writer), Joe Phillips (pencils), Tom Christopher, Bob Almond, Sam De La Rosa, Ariane Lenshoek, Mike Deming & Pat Redding (inks), Craig Anderson (editor)
Avengers I#238 (December, 1983) - Roger Stern (writer), Al Milgrom (pencils), Joe Sinnott (inks), Mark Gruenwald (editor)
Avengers I#243 (May, 1984) - Roger Stern (writer), Al Milgrom (pencils), Joe Sinnott (inks), Jim Shooter (editor)
Hercules: Prince of Power II#3 (May, 1984) - Bob Layton (writer/artist), Bob Budiansky (editor)
Avengers I#249 (November, 1984) - Roger Stern (writer), Al Milgrom (pencils), Joe Sinnott and others (inks), Jim Shooter (editor)
Avengers I#253 (March, 1985) - Roger Stern (writer), Bob Hall (pencils), Ian Akin & Brian Garvey (inks), Mark Gruenwald (editor)
Solo Avengers#16 (March, 1989) - Peter Gillis (writer), Don Perlin (pencils), Jack Abel (inks), Mark Gruenwald (editor)
Solo Avengers#18 (May, 1989) - Peter Gillis (writer), James Brock (pencils), Roy Richardson (inks), Mark Gruenwald (editor)
Infinity Gauntlet#1-2 (July-August, 1991) - Jim Starlin (writer), George Perez (pencils), Joe Rubinstein (inks), Craig Anderson (editor)
Silver Surfer III#52 (August, 1991) - Ron Marz (writer), Ron Lim (pencils), Tom Christopher (inks), Craig Anderson (editor)
Quasar#59 (June, 1994) - Ron Marz (writer), Andy Smith (pencils), Ralph Cabrera (inks), Mike Rockwitz (editor)
Cosmic Powers#4 (June, 1994) - Ron Marz (writer), Ron Lim (pencils), Bob Almond (inks), Craig Anderson (editor)
Ka-Zar IV#10 (February, 1998) - Mark Waid (writer), Andy Kubert (pencils), Jesse Delperdang (inks), Matt Idelson (editor)
Warlock IV#1 (November, 1998) - Louise Simonson (writer), Paschalis Ferry (pencils), Mark Morales (inks)
Thunderbolts I#46-47 (January-February, 2001) - Fabian Nicieza (writer), Mark Bagley (pencils), Greg Adams & Scott Hanna (#47) (inks), Tom Brevoort (editor)
She-Hulk II#6-7 (May-June, 2006) - Dan Slott (writer), Will Conrad (artist), Tom Brevoort (editor)
She-Hulk II#12-13 (November-December, 2006) - Dan Slott (writer), Rick Burchett (penciler), Cliff Rathburn (inker), Tom Brevoort (editor)
Fantastic Four III#546-547 (July-August, 2007) - Dwayne McDuffie (writer), Paul Pelletier (penciler), Rick Magyar, Scott Hanna (inkers), Tom Brevoort (editor)
Guardians of the Galaxy II#9 (March, 2009) - Dan Abnett, Andy Lanning (writers), Brad Walker, Carlos Magno (pencilers), Victor Olazaba, Jack Purcell (inkers), Bill Rosemann (editor)

First Posted: 02/13/2005
Last updated: 02/21/2009

Any Additions/Corrections? please let me know.

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