Dr. Henry “Hank” Pym developed a series of capsules containing the Pym Particles which he used to grow or shrink to various heights; he also developed capsules that enabled him to grow to greater than normal heights. Thereafter, Pym preferred to use his power to grow to giant size for crime fighting, and called himself Giant-Man. At first he found that he could not support his own weight if he grew to a height above twelve feet. Later, he was able to reach far greater heights, even 100 feet, and still move about comfortably, but he became weaker in proportion to the amount he grew beyond twelve feet.
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