Warning! Spoilers ahead for Batman/Superman: World’s Finest #12!It seems that Supergirl has finally settled the debate on which version of kryptonite is actually the most dangerous. An aside during a dreadfully awkward date has shed a light on a little known, but incredibly harmful, variant of the radioactive rock.

Though Superman and his fellow Kryptonians are some of the most powerful heroes in the DC Universe, there's one thing that weakens them considerably: Kryptonite, irradiated pieces of Clark's home planet that scattered everywhere throughout the galaxy after Krypton's destruction. Numerous pieces wound up on Earth, giving Superman's enemies ample opportunities to harm him. What's worse is kryptonite comes in several varieties, each with their own sinister effect. The classic green kryptonite causes Kryptonians pain, while gold can rob them of their powers. Red kryptonite is particularly insidious because its effects are completely random. It could simply depower Superman, or it could cause a drastic mutation.

Bizarro Red Kryptonite is a Nightmare According to Supergirl

But there’s a version of red kryptonite that’s even worse and Supergirl just finally revealed what it is. In Batman/Superman: World’s Finest #12 by Mark Waid and Emanuela Lupacchino, Wade Von Grawbadger, Tamra Bonvillain, Supergirl and Robin are recounting the terrible date they went on to their mentors. Dick Grayson kicks things off to a bad start arriving dressed in his Robin outfit, and things only go downhill from there when it becomes apparent that the two have almost nothing to talk about. The two attempt to make the evening work by trying to find good topics of discussion, only for Dick to begin bragging about his own skills. He cedes the conversation over to Supergirl, who begins listing various forms of kryptonite. When discussing little-known variations such as white and anti-kryptonite, she mentions "Bizarro red kryptonite", a variant of red that Supergirl implies only affects humans.

This odd type of red kryptonite made its first appearance in Superman’s Pal, Jimmy Olsen #80 and, true to Kara’s words, affects humans in the same way red kryptonite does on Kryptonians. Red Kryptonite isn’t as common as its green variation, but it’s always a gamble when Superman or his family is exposed to it, due to its highly unpredictable nature. While humans don’t have to worry much about kryptonite when exposed to it, something like Bizarro red kryptonite is a threat to nearly everyone on Earth.

Kryptonite That Can Affect Humans is Perfect For Superman's Enemies

If red kryptonite is able to cause drastic changes in the Man of Steel, just imagine how perilous the Bizarro variant could be in the hands of a villain who know how to handle it, like Lex Luthor or Metallo. They could use Bizarro red kryptonite in crowded places, causing numerous mutations, sudden onset of powers or even mass death. It’s already a nightmare scenario when a Kryptonian is exposed to red kryptonite, but a variant that can harm humans is almost unfathomable. Fans can hear more about kryptonite from Supergirl in Batman/Superman: World’s Finest #12, on sale now.

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