The Joker is a psychotic criminal from Gotham City. His appearance and personality is that of a clown, and he pulls tricks and assassinations that are deadly and clever. He is the archenemy of Batman, although he plays a minor role and makes occasional cameos in Teen Titans Go!.
The Joker was once a standard criminal who was foiled by Batman whilst in a chemical factory. During the struggle he fell into a vat of chemicals. This accident bleached his face white, dyed his hair green, turned his lips blood red, and gave him a permanent smile, transforming him into the Joker. His disfigurement also made him lose his sanity, and he would go on to become one of Gotham City's most feared supervillains.
The Joker usually dresses in purple, custom made clothes. He has a light green undershirt and a flower, which shoots acid. He has white skin, a pointy nose, and green hair. His overall appearance is based on a clown, as his name implies.
- Serious Business (Beast Boy dressed up)
- Real Boy Adventures (debut, cameo)
- Cool School (cameo on truck)
- Yearbook Madness (referenced in yearbook)
- Beast Man (cameo)
- 40%, 40%, 20% (cameo on cereal bowl)
- Pyramid Scheme (cameo)
- Batman v Teen Titans: Dark Injustice (cameo)
- The Titans Show (cameo)
- The Streak
- BBRAE (cameo as a painted face on a ferris wheel seat)
- TV Knight 2
- Mo' Money Mo' Problems
- Butt Atoms (cameo)
- Claus of the Batman (cameo on poster)
- The Joker's first design in this series is very similar to his revamped design from The New Batman Adventures.
- During the audio commentary on the Superman: The Animated Series episode "World's Finest" the producers state that they regret the stylistic change for the Joker, they also admit that removing his red lips was a mistake and that doing so was Teen Titans TV Series creator Glen Murakami's idea.
- In the DCAU and many other appearances he was voiced by Mark Hamill, who is best known for playing Luke Skywalker in the Star Wars films.
- At San Diego Comic Con 2017, Tara Strong stated that she would love it if Mark Hamill guest starred as The Joker in a future Episode.
- The Joker is one of the few characters to have multiple different design throughout the series.