In an attempt to regain the stolen super-soldier serum Extremis, Stark as Iron Man is injured battling a domestic terrorist, Mallen, who had been altered by the Extremis drug into a superhuman killing machine.
Seeing no other option, he took a modified dose of Extremis to heal his injures and improve his neural interface with the armor and other technologies. The revitalized Iron Man then set out after Mallen.
From that point on Tony utilized the Extremis in each of his armor designs and became accustomed to the power and convenience it provided.
During Marvel Secret Invasion, The invading Skrull queen Veranke infected Tony's body with a virus that shut down Extremis and the rest of Stark Tech. Tony believed the Extremis had been permanently rendered useless by the virus.
It wasn't until Tony deleted the contents of his brain, and installed an older version of his memories along with a new arc reactor, that he regained control and use of the Extremis. Using his newly designed suit titled "Bleeding Edge Armor", along with the energy supplied by his new arc reactor, Tony was able to utilize the Extremis to a greater extent.
This armor used vectored repulsor fields to tessellate its 'memory metal' design. The armor formed over a gold under-sheath produced by Stark's own body. The under-sheath's regenerative systems could repair damage to wearer or armor.
Due to Extremis, Stark's mind could now directly access satellite networks, security systems, and other digital technologies. The armor could be piloted remotely, even simultaneously with several other models in the field.
Repulsors were potent and had an additional "full form" version for multi-directional attacks. 
Standard weaponry such as the uni-beam, pulse bolts, and sonics were intact. Explosive "micro-munitions" were launched from the gauntlets.
The armor had a degree of adaptability to support and protect the wearer. A neural net could counteract or adopt similar effects to superhuman powers. 
Shields or "deflectors"  could be raised for additional defense.
The armor could maintain a cloaking effect.
Flight was now largely handed by small arrays throughout the suit; boots still contained turbines. The armor has reached speeds in excess of Mach 8.
A "gravity grip" produced by the gloves and soles could be produced for climbing surfaces or for anchoring. 
The armor may have had other systems yet to be revealed.
It was also extremely difficult to operate without the aid of the Extremis drug, described by Stark as being "like trying to fly six stealth bombers at once".
- ↑ Mighty Avengers 1
- ↑ Iron Man Vol 4 14, New Avengers 28
- ↑ they are called deflectors in Casey's minis. See Iron Man: The Inevitable and Enter The Mandarin
- ↑ Iron Man: The Inevitable 1
The Extremis Armor was one of the unlockable armors featured in the Iron Man movie-based video game.
- 268 Appearances of Iron Man Armor Model 30
- 77 Images featuring Iron Man Armor Model 30
- Item Gallery: Iron Man Armor Model 30
- Fan-Art Gallery: Iron Man Armor Model 30
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