Supergirl has fewer great villains in the Arrowverse, but there were some serious threats that caused Supergirl big problems ...

We've already seen what the green stuff can do time and time again, but now Supergirl is about to reveal what Red Kryptonite is and how it will effect our normally sweet-mannered Kara Danvers.

After being badly beaten by Reign in the 2017 finale, Supergirl began tonight’s ... who gained powers when exposed to an experimental “Kryptonite-X” and enjoyed the same flight, super ...

and Supergirl walks away. She gets dizzy for a moment, and her face gets red and glowy, but she shakes it off and flies away. A camera pan reveals a pile of red Kryptonite hiding beneath a ...

Tonight’s episode of Supergirl, titled “Falling,” will see Kara become infected with red Kryptonite. If you thought the green stuff was bad, just wait until you get a load of what this stuff ...

The conflict only escalated in "Shelter from the Storm" when Lena informed Supergirl that she'd learned the formula for creating kryptonite and had created some specifically designed to take down ...