Joker Toxin

Joker Toxin, also known as Smylex or Joker Venom, is a chemical compound developed by the Joker to aid in his various escapades.

Overview

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.