Kryptonite

<p>Kryptonite is a fictional material that appears primarily in <a href="/facts/Superman/1mQylpL6">Superman</a> stories published by <a href="/facts/DC_Comics/gvuKz3yL">DC Comics</a>. In its best-known form, it is a green, crystalline material originating from Superman's home world of <a href="/facts/Krypton_(comics)/fIUEY040">Krypton</a> that emits a unique, poisonous radiation that can weaken and even kill <a href="/facts/Kryptonian/a609fHkD">Kryptonians</a>. Kryptonite radiation can be transmitted through any element except <a href="/facts/Lead/EYljasJN">lead</a>. There are other varieties, such as red kryptonite and gold kryptonite, which have different but still generally negative effects.
</p><p>Adversaries of Superman and other characters are frequently depicted using kryptonite against Superman, with <a href="/facts/Lex_Luthor/BFWq1WLU">Lex Luthor</a> incorporating it into weapons, <a href="/facts/Metallo/prWalNSU">Metallo</a> being powered by it, and <a href="/facts/Titano/BouHXL0b">Titano</a> able to project its radiation from his eyes. Due to Superman's popularity, kryptonite has become a byword for an extraordinary exploitable weakness, synonymous with "<a href="/facts/Achilles%2527_heel/KVpYCRBV">Achilles' heel</a>".
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Kryptonite open-in-new

Kryptonite