Iron Man was one of the earliest superheroes that set the base for today's vast MCU. Almost everyone is familiar with the eccentric billionaire behind the Iron Man suit, Tony Stark. The Iron Man suits aren't the only major inventions in Tony's catalog. Both Tony and the Iron Man suits are shown to have an arc reactor in the middle of their chest.

While the Arc Reactor does charge up the Iron Man suits, it is also necessary to keep Tony alive. With new versions of Iron Man suits, Tony also continued to develop the Arc Reactor, and here are all the versions of the Arc Reactor that Tony used throughout the MCU and why he actually needs them.

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When was Iron Man's arc reactor created?

The Arc Reactor was made in the first Iron Man movie which was the first film in the MCU. During Tony's visit to Afghanistan to demonstrate one of Stark Industry's weapons, Tony is attacked and captured by a terrorist group known as the 10 Rings and gets caught in an explosion by a missile made by none other than Stark Industry themselves. This sends shrapnel into Tony's chest which causes him to pass out. Upon waking up, Tony finds himself held captive by the terrorists who then order Tony to build a missile for them.

Yinsen, a fellow captive in the cave, designs a battery-powered magnet that keeps the shrapnel from piercing Tony's heart. With the help of Yinsen, Tony makes a miniature arc reactor that would power the electromagnet to keep the shrapnel from entering his heart. The makeshift Arc Reactor is actually based on the same very same Reactor powering the Stark Industry factory. The first Arc Reactor was capable of outputting a whopping 3 gigajoules per second that could run a human heart for 50 lifetimes. While the terrorists thought that Tony was building a Missile, he was actually working on the very first Iron Man suit that would be powered by the same Arc Reactor and was his ticket back home. However, it is worth noting that the Arc Reactor doesn't supply an unlimited amount of energy, the power supply varies from model to model. For example, the first concept model could only charge the first Iron Man suit for a mere 50 minutes. However, the supply was increased with newer Arc Reactor models.

How many versions of Iron Man's arc reactor have there been?

Throughout the MCU, Tony Stark has been shown using different versions of the Arc Reactor, each improving upon the previous version. The initial Palladium Arc Reactor Mark I, crafted during his captivity in Afghanistan, established the foundation for subsequent advancements which served both a power source and instrumental in creating the first Iron Man suit.

Progressing from there, the Palladium Arc Reactor Mark II saw improvements in miniaturization, later employed when Tony unveiled his inaugural functional Iron Man suit in IronMan 1. As the events unfolded between Iron Man and Iron Man 2, the Palladium Arc Reactor Mark III emerged, refining the technology even further and addressing the shortcomings of the Mark II.

However, a pivotal moment occurred in Iron Man 2 when Tony devised a groundbreaking new element for the Arc Reactor, abandoning palladium due to it slowly poisoning him. This ushered in the era of the New Energy Arc Reactor Mark I, a revolutionary clean energy source crafted with guidance from recorded messages left by his father, Howard Stark.

The New Energy Arc Reactor Mark II took center stage in Iron Man 3, which also powered the Iron Legion suits, an army of Iron suits. Palladium Arc Reactor Mark III was used to power the Hulkbuster suit in Avengers: Age of Ultron which was strong enough to take down the Hulk. Palladium Arc Reactor Mark IV was used shortly on-screen powering the Mark 46 and 47 suits that appeared in Spider-Man: Homecoming.

Yet, the most significant breakthrough came in Avengers: Infinity War, where the New Energy Arc Reactor V was the most advanced even accommodating Nanoparticles and wielding enough energy to power canons. This advancement paved the way for the ultimate version, the New Energy Arc Reactor VI, utilized by Tony Stark in Avengers: Endgame. In this climatic showdown, the New Energy Arc Reactor VI, though slightly larger, provided the Iron Man suits with enough power even to go head-on against Thanos himself.

Iron Man's Arc Reactor's Meaning At Tony Stark's Funeral

Tony Stark is undoubtedly one of the most complex superheroes in the MCU. His journey from arrogance and selfishness to profound personal development stands as one of the finest character progressions in the MCU. He would often use people for his own gain which led to conflicts, like the creation of Ultron. However, despite his harsh methods, his underlying intentions are aimed at achieving the greater good.

Pepper Potts, once Tony's assistant and now his wife, truly comprehends the man behind the iconic suit. A powerful moment occurs when she gifts him his former arc reactor, enclosed in a glass case labeled 'Proof That Tony Stark Has A Heart.' This gesture highlights the significance of the arc reactor, which was initially designed to prevent shrapnel from reaching his heart. It challenges the misconception of Tony as heartless due to his selfish and arrogant demeanor. Over time, especially after his sacrificial act in Avengers: Endgame, it becomes evident that Tony was always striving to be a better man who genuinely cares about others.

The same arc reactor reappears during Tony's poignant funeral at the conclusion of Avengers: Endgame. Placed by the riverside by Pepper, it serves as a meaningful homage to the fallen hero, a loving husband, and a devoted father. This act not only pays tribute to Tony's intellect but also underscores his capacity for compassion, symbolizing his ultimate sacrifice for the greater good of humanity and the universe.

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