Short answer: Excluding Kira Yamato’s plot armor, Athrun Zala using the Justice is more likely to win due to him being less emotional, more rational, and more decisive than Kira Yamato. Although the Freedom is a very fast machine because of its HiMAT system, the Justice is also equipped with the same system making the Justice just as a fast machine as well.
Both mobile suits come from ZAFT. They were manufactured during the first Alliance – PLANT ware, in secret, as a retaliation of the PLANTs towards the Earth Alliance’s use of nuclear weapons.
Both machines were the most powerful and advanced mobile suits during the late stages of the first Alliance – PLANT war and during the middle stages of the second Alliance – PLANT war.
Compared to regular mobile suits that were mass produced during the time such as JINNs, DINNs, and the Strike Daggers, the Freedom and the Justice had far more power because unlike the other mobile suits, that were powered by battery cells, the Freedom and the Justice were powered by nuclear fusion reactors.
This meant that both the Freedom and the Justice had at least 4 times as much power compared to regular mobile suits. This also meant that the Freedom and Justice were able to last longer in battles without having to resupply.
The production of these machines was classified information. This is because the nuclear fusion reactor, that supplied power of both machines, was a direct violation against the treaty between the Alliance and the PLANTs to never use nuclear weapons again.
In order to enforce the non-usage of nuclear weapons, the PLANTs barraged the Earth with numerous N-Jammers or Neutron – Jammer, making them embedded deep within the Earth’s crust. This lead to a serious power crisis on the Earth but it enforced the non-usage of nuclear weapons.
If the Earth Alliance were to discover the secrets of the Freedom and the Justice, it would place the PLANTs in a very bad position as it would mean that the Earth Alliance would now know the secrets of the N-Jammer Canceler or Neutron-Jammer Canceler.
Such an event could give rise to the possibility of the Earth Alliance producing nuclear powered mobile suits, which would lead to a more destructive and lengthier war.
To prevent such an event, the PLANT Supreme Council Chairman Patrick Zala, ordered Special Forces Athrun Zala, to recover the Freedom and kill anyone who has come into contact with the mobile suit and the pilot. Chairman Patrick Zala saw it only fit to exercise such extreme measures in order to contain the secret of the Freedom and the Justice.
Both machines were destroyed. The Justice was destroyed when Athrun Zala made it self-destruct in order to destroy Genesis, and The Freedom was destroyed by Shinn Asuka in Gundam SEED Destiny.
Given the fact that they come from the PLANTs, and the fact that they were meant to be assigned to the same ship, the Eternal, we can see that the development of these two mobile suits came with the idea that once compliments the other.
Both machines were designed with specific fighting capabilities but with the intent of filling in for where the other machine lacks. These were manufactured by ZAFT as super-weapons with the intent of ending the war.
ZGMF – X10A FREEDOM
From the design of The Freedom and from what we see from the anime, the Freedom was designed to be a mid-range to long –range mobile suit. The Freedom excels at mid-range to long-range due to its many beam cannons, specifically, two positron cannons mounted on its shoulders, two railguns that are mounted on the waist, and two hand-held beam rifles.
That makes a total count of four beams and two railguns. Significantly more than the average mobile suit that only carries one beam rifle.
The railguns of the Freedom gives it an edge when fighting over water as shots from railguns can penetrate water while beams do not.
Beams appear to be more penetrative compared to railguns though as seen when Kira, using the Freedom, uses the railguns on the Destiny. The result is a mere blast that does not do any significant damage to the Freedom however the pilot of the Destiny, Shinn Asuka, makes a comment, “If those were beams, then this would be over already. Is that what you’re trying to tell me?! Is that what this is a lesson?!”
The Freedom excels at mid-long range fighting but that does not mean it not good with close combat. Equipped with the High Mobility Aerial Tactics (HiMAT) system, the Freedom was the fastest machine during the first Alliance – PLANT war.
This speed made it possible for the freedom to get into close range with its opponents and to add to its advantages, the freedom may or may not hold a physical shield because it has a laminated anti-beam shield mounted on its left forearm. This enables the freedom to hold two beam sabers which made the Freedom, with the right pilot, an extremely dangerous machine to be in close combat with.
ZGMF – X09A JUSTICE
On the other hand, the Justice was designed as a melee specialist. We can tell based on the design of the machine. Although it is also equipped with the HiMAT system, it is not as fast as the freedom. However with its many beam sabers and beam boomerangs, the Justice is second to none when it comes to close combat.
The Justice is also equipped with two small rapid-fire guns mounted on its head. Although these guns are small compared to the size of the beam rifle and the size of the minigun of the duel, these guns are enough to stop enemy mobile suit movements during close combat.
The Justice was not designed for mid-long range combat but it has capabilities to fight in these conditions. The machine is equipped with one beam rifle, two beam cannons, and two beam boomerangs.
A very interesting component of the Justice is its backpack module which serves two purposes. When attached, it gives the Justice use of the HiMAT system which makes the machine fly faster than the average mobile suit in space or in the atmosphere.
Its backpack, called the Fatum-00, can also be detached and be used as a support unit. It is mounted with two beam cannons, two turret machine guns, and four fixed machine guns. With these armaments, the Fatum-00 can prove to be enough to be at least a distraction for enemy mobile suits just before the Justice closes the distance to eliminate its target.
As a pilot, Kira Yamato has always been limited by his emotions. Although he possesses unmatched potential as a mobile suit pilot due to him being the ultimate coordinator, his kind nature and indecisiveness limit his skills in battle.
Due to his pacifist nature, Kira Yamato refuses to kill his enemies unless he needs to. In battle, he only aims for the head piece or the limbs. This battle style was deduced by Ray Za Burrel and was used by Shinn Asuka to defeat the Freedom in Gundam SEED Destiny.
Because his emotions play a big role in his fighting style, Kira Yamato frequently enters SEED mode using the first method, with the SEED falling and then breaking.
When Kira Yamato Pilots the Freedom, he takes advantage of the mid-range to long-range capabilities of the machine. He usually fights using his beams and railguns unless he needs to fight in close combat.
Compared to Kira Yamato as a mobile suit pilot, Athrun Zala is more rational and decisive. He uses his logic more that his emotions when in battle. Before Athrun Zala joined Kira Yamato’s cause, he did not find any difficulty in shooting down his enemies. The only enemy that Athrun ever found difficult to shoot down was his childhood friend, Kira Yamato.
When piloting the Justice, Athrun never lost a battle. Although the Justice was designed for close combat, he usually prefers to fight mid-range using his beam rifle and beam cannons. However for much stronger opponents, like Shinn Asuka, Athrun Zala prefers to fight in melee using his beam saber.
When he fights in melee, the Justice usually takes two beam sabers and attaches both handles of the beams sabers together to form a double-bladed beam saber held in one hand. The other hand will then hold a physical shield.
With the exception of Kira Yamato’s plot armor, we believe that Athrun Zala, using the Justice would win this battle as he would be able to find a way to close the distance between the Freedom and the Justice.
Given the fact that they know each other well and have fought each other in the past and have fought alongside each other as well, makes it clear that Athrun Zala knows how Kira Yamato fights.
Although the Freedom is a very fast machine, the Justice is also equipped with the HiMAT system which makes the Justice a fast machine as well.
In Gundam SEED, Kira Yamato and Athrun Zala have already fought each other to the death, and from how it went, it is pretty clear that Athrun Zala would have won if his machine did not run out of power.
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