(Green) Kryptonite is crystaline material which emits a radiation that depowers, weakens, nauseates and even kills Kryptonian beings who otherwise have superpowers on Earth. The substance's only clear weakness being lead which cancels out its powers. Over time, the radiation can also cause cancer in the cells of non-Kryptonian beings which has resulted in Batman keeping it in a lead-case.
The Kryptonite used to create Batman's Kryptonite ring first traced back to having been on display in an exhibition hall. The kryptonite was then stolen by a derranged, paranoid scientist named Prof. Emmet Vale who was convinced that Superman was the beginning of an alien invasion.
To steal the Kryptonite, Vale employed John Corben AKA Metallo. Metallo being a criminal who Vale transplanted the brain of into a robot body made of the near-invincible metal metallo after John was injured in an accident he blamed Superman for. The cybernetic body was powered by a Uranium heart that needed to be replaced every 2 days by Vale, forcing Corben's loyalty to the mad professor. Due to his hatred of Superman, Vale replaced Corben's uranium heart with the chunk of Kryptonite which provided Metallo with an endless supply of radioactive energy.
Metallo went on to kill Vale as he was freed from the professor's grip and use his new heart to try and get revenge on Superman for making him lose his human body.
After observing Superman's weakness to Metallo's heart, Superman's arch-nemesis Lex Luthor kidnapped Metallo. With the help of one Dr. Happersen, Luthor ripped the kryptonite out from Corben's chest. Following this, Luthor used a piece of the kryptonite to construct the Kryptonite Ring which was made to keep Superman away. Luthor would go on to wear this ring at all times.
Of-course, the constant exposure to the ring caused Luthor to contract cancer which spread from his hand to the rest of his body. Luthor had his hand amputated but to no avail and ultimately was forced to genetically clone himself and transfer his consciousness into the body of his clone.
Dark Knight over Metropolis
Following Lex's contraction of cancer, the ring was stolen by LexCorp computer-scientist Amanda McCoy who had previously used a super-computer to determine that Superman was Lex Luthor; a statement which Lex refused to believe and disdained her for making.
Determined to prove her theory, Amanda arranged to meet Clark Kent in a cemetery where she had secretly smuggled the ring. When Clark appeared, she used the ring to trigger her weakness and in-doing so proved that he was in-fact Superman. However, on her way back to LexCorp she passed through Metropolis' slums where she was mugged and murdered by a couple criminals.
The ring was then pocketed by a homeless man who later moved to Gotham City where he was subsequently murdered himself. This all lead to Batman becoming involved in the murders and a conspiracy which involved LexCorp and the criminal-syndicate Intergang in Metropolis, forcing Batman to team up with Superman. After the adventure, Batman would come to give the ring to Superman which made Superman trust Batman more than ever. As such, Superman later visited Bruce in the Bat-Cave and gave him back the ring, saying that if he ever lost control he trusted Batman to use the ring to stop him.
Batman kept the Kryptonite Ring in a lead container in the batcave, usually as a sort of trophy in storage. Sometimes bringing it on missions where it was concealed in his utility belt.
Batman's most notable usage of the weapon occured in Metropolis whenPoison Ivy (under the employ of Hush) used a mutant plant to latch onto Superman's body while he was affected by her kryptonite lipstick and brainwashed him into being her loyal, lovebound slave. When Batman and Catwoman tracked down Ivy, she used Superman to fight Batman and try to kill him and Catwoman.
To combat this, Batman revealed that he brought the ring and used it to fight Superman by delivering serious blows. All the while Batman and Catwoman hid in Metropolis' lead-lined tunnel ways which were built by Luthor to hide them from Superman's x-ray vision. Ultimately Batman won by reigniting the humanity within Clark, allowing him to break free from Ivy's control.
Appearances in Other Media
- Batman: The Brave and the Bold: In this show it is seen in the possession of Lex Luthor.
- Smallville: The ring appears in the series with effectively the same history as in the comics.