Every MCU Villain Ranked Weakest To Strongest

Another embittered enemy of Tony Stark, Aldrich Killian was an awkward businessman and inventor who was (quite literally) left in the cold by Stark before he became Iron Man. Feeling betrayed, he helped create Extremis, a complex and deadly form of genetic mutation that uses nanotech to help the human body heal and grow passed its normal level of strength.

Creating an army of Extremis-infused terrorists, Killian made plans to take over America, and thanks to his immeasurable power of regeneration, ability to breathe fire and spotless fighting skills, he was able to hold his own against Iron Man and the Iron Legion. He may have finally been put down by Pepper Potts, but Killian was a villain who seemed almost indestructible, and had the power to back it up.