- " I suppose so. After all, I'm an animal; Not a monster."
- —Point Laser Point
Sylvester made his first appearance, though only a silent cameo in Jailbird and Jailbunny, during the song Blow My Stack, when Yosemite Sam was singing about not being able to count to ten at an anger management class.
In Devil Dog, Sylvester was chasing after Tweety, and just when he catches up to him, the Tasmanian Devil, as a twist to the usual antics, shows up and Tweety notices that Taz is behind Sylvester and says "I tawt I saw a Tasmanian Devil". Sylvester doesn't believe Tweety and grabs him. Taz is right behind Sylvester ready to eat them both. Sylvester notices and start running away from him. Tweety and Sylvester manage to escape Taz, by running to the kitchen, as he ate the table and Tweety flying away up the chimney with Sylvester on his legs. After Taz falls back to Daffy and Bugs, they both run back inside of Granny's mansion.
In Eligible Bachelors, Sylvester tries to catch Tweety with a golf club, but he landed in the chimney. He later appeared in the end when Tweety tells him that he fought in World War II and also tells him Tweety's gender.
- " Oh. I guess I was wrong."
- —Eligible Bachelors
- " Yeah? Well, I let you get away most of the time...gotta have something to do around the old lady's house."
- —Sylvester to Tweety
One of his major appereances is in the episode Ridiculous Journey where him, Taz, and Tweety are seperated from their owners. They are moved all the way to Alaska and have to go on a long epic journey back home while at the same time avoiding from being caught by the hunter Blacque Jacque Shellacque.
In The Grand Old Duck of York, he is seen in Granny's house, paralyzed by a Daffy's horrific piano songs.
- 103. Jailbird and Jailbunny (debut/Merrie Melodies)
- 108. Devil Dog
- 110. Eligible Bachelors
- 112. Double Date (Merrie Melodies)
- 113. To Bowl or Not to Bowl (Merrie Melodies)
- 114. Newspaper Thief (cameo in Merrie Melodies)
- 126. Point, Laser Point
- 210. A Christmas Carol (cameo)
- 211. We're In Big Truffle (cameo)
- 214. The Black Widow (cameo)
- 217. Gribbler's Quest (Merrie Melodies)
- 218. The Grand Old Duck of York (cameo)
- 219. Ridiculous Journey
- Even though Sylvester appeared in The Jailbird and Jailbunny, his first speaking role was in Devil Dog.
- Sylvester claims that he lets Tweety get away most of the time, so he doesn't get bored.
- Sylvester has evidently been given a style change since his last series appearance: He has gained a more slender, shorter body and his canine teeth have become more prominent and sharp, making him appear more like a housecat. In Season Two he resembles more like his classic-era counterpart.
- Like Daffy, he has a lisp when he speaks.
- Sylvester has both a mother and a brother, revealed in Point, Laser Point.
- Jeff Bergman (US)
- Masashi Ebara (Japan)
- Alfonso Ramírez (Latin America)
- Michael Pan (Germany)
- Guy Rushiniak (Israel)
- Armand Calotă (Romania)
- Τάσος Κωστής (Greece)