One Supergirl Villain Proved Which Kryptonite is Deadliest

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For all the many variants of kryptonite there are, an adversary of Supergirl's proved that one is surprisingly the most effective. Green may be the most common version, but a lesser-seen type can be the deadliest when in the wrong hands.

After Krypton's devastating explosion, shards of the planet were scattered throughout the universe. These little pieces of Superman and Supergirl's home world were transformed into kryptonite and became one of the most widely known Achille's heels for Kryptonians. The most classic version of the rock comes in its green form and exposing Superman to kryptonite could have deadly effects. But green is just one type of the radioactive meteorite. Kryptonite has also come in other forms such as red, gold, and various synthetic variants. What makes kryptonite such a threat is that each version has it's own effect on Kryptonians, with some being being much deadlier that others.

Related: Supergirl Could Actually Give Anyone Superman's Powers

Supergirl's occasionally recurring nemesis Reactron made a strong argument for which form is actually the strongest in Superman #683 by James Robinson, Renato Guedes, and Jorge Correa, Jr… As part of a covert military effort, Reactron is drafted to take out Kryptonians that have taken residence on Earth. He’s partnered with Superman’s kryptonite-powered villain Metallo, who uses his trademark green kryptonite heart to do some damage. Reactron, on the other hand, is given a gold kryptonite heart. While it's not as lethal as the green variant, gold can depower a Kryptonian for fifteen seconds, or as Reactron says "plenty of time to take care of business". After stripping innocent Kryptonians of their abilities, Reactron brutally slaughters them with lasers. He