Joker Toxin, also known as Smylex or Joker Venom, is a chemical compound developed by the Joker to aid in his various escapades.
A highly aggressive poison, the compound causes the victim to laugh uncontrollably before dying; their facial muscles pulled taut in a rictus grin.
Originally a gas, the compound has since been developed into additional liquid and powder forms. The Joker is also able to effectively create the compound through the combination of various, otherwise safe, articles.
- As part of the gang war erupting in Gotham City, the Joker has T.O. Morrow develop a new strain of Joker Venom.
- Using Ace Chemicals as his base of operations, T.O. Morrow uses the compound to create his own army of mutant clowns.
- As he is with most chemicals, the Joker is normally immune to his own toxin.
- The effects of Joker Toxin is similar to the legendary Sardinian Cabbage which supposedly causes laughter until the point of death.