GAT-X303 Aegis Gundam

GAT-X303 Aegis Gundam

The GAT-X303 Aegis Gundam is a transforming Mobile Suit that appears in the Mobile Suit Gundam SEED series, this MS is piloted by Asran Zala.

This MS is one of five OMNI MS prototypes as part of its Armes G project, it will be stolen by ZAFT during an attack by the LeCreuset squadron.


Designated as the Alliance's Project G command unit due to

its enhanced communication and analysis capabilities, the Aegis also has heavy attack power as well as Phase Shift Armor, it can also transform into Mobile Armor (MA) due to its X300 chassis. In MA mode, it has two different sub-modes, 'Cruise' and 'Attack'. In 'MA Cruise' mode, Aegis has higher speed and acceleration, while in 'MA Attack' mode, he can destroy the enemy ship / Mobile Suit with his "Scylla", a 580mm energy cannon directly. He has the ability to grab his enemies with his four limbs, and destroy them with the cannon. Other weapons include two head-mounted CIWS, a 60mm High Energy Rifle, a shield, and Beam Sabers in each limb.

Aegis also has a large sensor on top of its head and unlike most MS its main thrusters appear to be located in the side storages on its waist. Due to the transformation system, the internal structure of the Aegis is more complex and it is for this reason that there are no mass production variants of the MS. The three different modes (MS Mode, MA Cruise Mode and MA Attack Mode) also mean that the pilot of the Aegis needs higher skills to be able to use the Mobile Suit effectively.

  • Phase Shift Armor

Like all Project G machines, the Strike is equipped with phase shift armor called Phase Shift. When this armor is activated, the Strike's color changes from light gray to red. Phase Shift armor makes the Strike immune to physical attacks such as bullets, sword slashes, missiles, etc. However, the Phase Shift continually drains battery power, reducing the MS's stamina in combat, and consumes additional power when hit.

  • Launcher

The Aegis Gundam's forearms feature an integrated launcher, designed to fire a remote transmitter and broadcast an SOS in an emergency.


  • "Igelstellung" 75mm Automatic Mutli-barrel CIWS: Anti-aircraft guns mounted on either side of the head. These light projectile weapons are used to intercept missiles, destroy lightly armored vehicles, etc.
  • Beam Saber: Aegis possesses a total of four Beam Sabers, these being located in his forearms and feet. All four can be used simultaneously, whether in Mobile Suit or Mobile Armor.
  • Shield: A simple anti-beam coated shield that can be mounted on the left forearm or handheld. It is stowed on the side mounts when not in use and when the MS converts to MA Attack/Cruise mode.
  • "Scylla" 580mm Multi-phase Energy Cannon: A powerful energy cannon that can only be used when the Aegis is in Mobile Armor mode. It is the beam weapon with the largest caliber to be fitted to a Project G MS (Project G) and likely to be the most powerful, it has enough power to pierce the full width of a ship of Earth Alliance fight.
  • 60mm High Energy Beam Rifle: The Aegis' high energy rifle, it is his main weapon when in Mobile Suit mode, he carries it in his hand when in MS mode, and it is placed on the in MA mode.


  • GAT-X303AA Rosso Aegis: The GAT-X303AA Rosso Aegis is a modified model of the Aegis Gundam produced under "Project Actaeon", a joint development between several companies led by Actaeon Industries and Phantom Pain. The GAT-X303AA Rosso Aegis ("AA" stands for "Advanced Acceleration") retains most of Aegis' original weapons except for the shield and head which has its Vulcans removed, it has Phase armor Shift and a more complex transformation mechanism. Besides "MS mode", "Cruiser MA mode" and "Attack MA mode", it can also transform into 3 other modes. However, these additional modes have made the internal structure of the Rosso Aegis more complex and therefore a cause for concern. In addition, the pilot must also have a higher skill level to be
    able to use the different modes effectively. Although the MS is battery-powered, Phantom Pain plans to convert it to a nuclear unit and has already reserved space in the MS to be able to transition. The main changes to the MS are the replacement of the side packs with normal side armor, and the addition of a pair of rear mounted wing packs, which increase the mobility of its MA modes and allow the Rosso Aegis to transform into its new "Flight mode". In this mode, the wing packs are positioned over the shoulder and mimic Jet Striker gear, allowing the Rosso Aegis to fly through the atmosphere in MS mode. Another new mode is "Shooting mode", which allows the Rosso Aegis to fire its "Scylla" cannon in MS mode by raising the front torso section, which cannot be done with the original Aegis. Additionally, the beam of the "Scylla" is deviable thanks to the magnetic field generators mounted in the wing casings, which can be positioned on the sides of the barrel. The last new transformation mode is "Multi-leg mode", whereby the Rosso Aegis retains the use of the upper body of the MS mode while having the mobility of a four-legged MA. In this mode, the legs are bent nearly 90° while the wing casings are flipped upside down, with the upper components turning into a set of additional legs.
  • GAT-X303 Aegis Gundam (Atmospheric Equipment): Appearing in the manga Mobile Suit Gundam SEED Re:, it is the Aegis Gundam equipped with new modules that allow it to transform into MA mode usable in the atmosphere. Here are the changes to MS:
    1. Side packs are replaced with wing packs which mount one linear cannon each,
    2. The MS can now fire its 580mm “Scylla” multi-phase energy cannon in MS mode.
    3. The shield is modified with three additional Beam Saber integrated into it.
    4. It uses a bigger and longer rifle as its main handheld weapon, in the new MA mode this beam rifle is connected to the "Scylla" 580mm Multi-phase Energy Cannon.


One of five Mobile Suits created as part of the Atlantic Federation's Project G. The Aegis was deployed on January 20 CE71 ( Cosmic Era ), along with the other MSs from the same project. Stored in the Heliopolis colony, it became the target of ZAFT and was stolen on January 25 along with the other models except the GAT-X105 Strike Gundam . Its pilot was Asran Zala, who used the Gundam for several months.

The Aegis was transported to Earth shortly after the battle that took place in orbit on February 13 to pursue the Archangel. It was held at the Carpentaria base in Australia until the Archangel crossed the Indian Ocean, where it was sent to join the Vosgulov-class submarine, the Cousteau. The GAT-X303 Aegis, GAT-X102 Duel Gundam , GAT-X103 Buster Gundam and GAT-X207 Blitz Gundam managed to intercept the Archangel in the middle of the ocean and forced the heavily damaged ship into hiding in Orb for repairs.

His last battle was in mid-April, when he fought Kira Yamato in the GAT-X105+AQM/E-X01 Aile Strike Gundam and Tolle Koenig in his FX-550 Skygrasper during the Battle of the Marshall Islands. There, Asran destroyed the Skygrapser, killing Tolle, and fought Kira to the death. At the climax of the battle, Asran self-destructs the Aegis after capturing the Strike with his MA Mode, destroying the Aegis and heavily damaging the Strike. He ejected shortly before and was found injured on the bank by Cagalli Yula Athha. Asran

returned to combat soon after, piloting the ZGMF-X09A Justice Gundam.

The fragments of the destroyed Mobile Suit eventually found a final, peaceful use as a playground for young children, on the same island where Asran and Kira fought. His shield was later salvaged and auctioned off on the black market for scrap, a fact which has been documented by Lowe Guele and his friends. The Aegis was used as the base unit to develop ZAFT's ZGMF-X11A Regenerate Gundam.

After the war, as part of the "Project Actaeon" MS plan development, another Aegis Gundam was manufactured and flown by Phantom Pain pilot Emilio Bloderick. The unit was then upgraded to GAT-X303AA Rosso Aegis.

Did you know?

  • As seen in the episode "Flashing Blades" (Episode 30 of the Original Edition, 28 of the HD Remaster), the Aegis' self-destruct code is 2-8-8-7.
  • The GAT-X303 Aegis Gundam is the only Project G MS not to have been adapted into MS Mass Produced, or re-created by the paramilitary organization Librarian Works.
  • Aegis comes from ancient Greek Aegis who in French himself gave the word aegis. Relating to the shield used by Zeus in Greek mythology. It can also be compared to the shield of Athena in mythology, which in the illiad produces a sound comparable to the roar of thousands of dragons.
  • The GAT-X303AA Rosso Aegis Gundam bears, like its sister units the GAT-X105E Strike Noir Gundam, GAT-X1022 Blu Duel, GAT-X103AP Verde Buster and GAT-X207SR Nero Blitz, a color name, "rosso" means "red" in Italian and is a reference to its color scheme.
  • The choice of the red color for the Aegis Gundam and its speed in its Cruiser MA mode are a reference to another famous character from the Gundam saga, namely Char Aznable .
Back to blog

Leave a comment

Please note, comments need to be approved before they are published.