1 Zim - Invader Zim
Zim is the titular protagonist and anti-hero of the American animated series Invader Zim, created by Jhonen Vasquez for Nickelodeon.
Technically, he's a villain protagonist. - ModernSpongeBobSucks
He is the main character, but he's still the antihero in his show.
He acts like a moron, but he's really a genius. He WAS a scientist and he DID pass Invader training.
I don't know why people think he is younger than Tak though. He was already an Invader when Tak was testing to be an Invader.
PLUS he was a scientist before that too.
2 Sheldon J. Plankton - Spongebob Squarepants
Sheldon James Plankton, or simply Plankton, is a character in the Nickelodeon animated television series SpongeBob SquarePants.
My Favorite antagonist characters of my favorite cartoon! Plankton is funny! So vote it now. thanks.
Manages to be antagonistic but likable. - Garythesnail
He's my favorite antagonist of all time. - happyhappyjoyjoy
3 Vicky - Fairly Odd Parents
Vicky is one of the two main antagonists of Nickelodeon's The Fairly OddParents. She is one of Timmy's most personal enemies and his remorseless, arrogant, and cruel babysitter.
She's very unlikable to be honest.
4 King Ramses - Courage the Cowardly Dog
Does this ring a bell"return the slab" - happyhappyjoyjoy
5 Mom - Futurama
6 Bill Cipher - Gravity Fall
Bill Cipher is a triangular dream demon formerly existent only in the mindscape who wished to gain access to the real world. He has been running amok in Gravity Falls, Oregon since being summoned by Stanford Pines over thirty years ago. He is known for his mysterious demeanor and sadistic humor. He ...read more.
He's like an epic boss for video game hard to think he's in a kidshow. Honestly, this is the only show I root for the protagonist. - happyhappyjoyjoy
He's not annoying and dumb like most cartoon characters. He is funny! 👍
Best villain ever!
Trickster, good appearance, just WOW!
And his look, love that.
7 Angelica - Rugrats
She was my favorite character. I don't know why but I always like the evil characters the best. - happyhappyjoyjoy
8 Summerween Trickster - Gravity Falls
9 Tom - Tom & Jerry
Thomas "Tom" Cat is a fictional character and one of the title characters in Metro-Goldwyn-Mayer's series of Tom and Jerry theatrical cartoon short films.
I always kind of wanted Tom to just eat Jerry. - happyhappyjoyjoy
10 Mojo Jojo - Powerpuff Girls
Mojo Jojo is a fictional character from the American animated television series, The Powerpuff Girls, created by animator Craig McCracken for Cartoon Network.
I right for the girls in this show. - happyhappyjoyjoy
11 Red Guy - Cow and Chicken
12 Eustace - Courage the Cowardly Dog
Eustace Bagge is a fictional character from the Cartoon Network animated series, Courage the Cowardly Dog.
13 Katz - Courage the Cowardly Dog
Katz is a fictional character from the Cartoon Network animated series, Courage the Cowardly Dog. He frequently appears as a recurring antagonist in the series . His first appearance was in the episode "A Night at the Katz Motel" .
14 Wayne Cramp - The Cramp Twins
15 Officer Dibble - Top Cat
16 HIM - The Powerpuff Girls
17 Yosemite Sam - Looney Tunes
Yosemite Sam is an American animated cartoon character in the Looney Tunes and Merrie Melodies series of cartoons produced by Warner Bros. Animation. The name is somewhat alliterative and is inspired by Yosemite National Park.
18 Mr. Blik - Catscratch
19 Garrett Bobby Ferguson - Regular Show
20 Skeletor - He-Man
21 Freaky Fred (Courage the Cowardly Dog)
Freaky Fred is a fictional character from the Cartoon Network animated series, Courage the Cowardly Dog.
22 Aku - Samurai Jack
Aku is a fictional character and the main antagonist of Samurai Jack, an American animated television series created by Genndy Tartakovsky for Cartoon Network.
"Worship me, Daughters of Aku! " - ModernSpongeBobSucks
23 Discord - My Little Pony: Friendship Is Magic
He's Really Funny - JPK
24 Frieza - DBZ
Freeza (Pronounced "Frieza" in the Funimation dub) is fictional character in the Dragon Ball series by Akira Toriyama as the primary antagonist of the Freeza Saga. He is a galactic tyrant who governs the Planet Trade Organization and is feared by the universe for his sadistic and brutal nature. He is ...read more.
25 I.R. Baboon - I Am Weasel
26 Dr. Vindaloo - Courage the Cowardly Dog
27 The Angry Scientist - Sheep in the Big City
28 Lionel Botch - Help! It's the Hair Bear Bunch
29 Elmer Fud - Looney Toons
30 Yellow Diamond - Steven Universe