- " Let's just say I'd "handle" the problem?"
- —Sunday Night Slice
Marvin the Martian is one of the main antagonists of the show. He is a former foreign exchange student from Mars who attended Daffy's high school. Marvin is still a nerdy misfit with a laser pistol. He owns a martian dog, K-9, and martian slaves, The Instant Martians.
Marvin has got a very strange outfit for a stereotyped martian extraterrestrial. He has a whole black colored face, in which only his eyes are visible and wears a green helmet very similar to those ancient romans warriors wore, which may be a reference to the fact he comes from Mars, a planet named after the war roman god. It's later revealed that the panache on his helmet is actually his hair coming out from a hole on its top. Aside his red shirt, he also wears what appears to be a green metallic skirt (possibly a roman militar skirt, another reference to the roman deity his planet is named after), white gloves and basketball shoes (like most of the other show's main characters).
- " I'm a Martian!
Not a great white shark.
I'm a Martian!
I play frisbee in the park."
- —I'm a Martian
Marvin the Martian first debuted in the episode, Members Only, where he sang his own Merrie Melodie about how being another planet inhabitant is hard because people will think you are a misfit. The song is called, I'm a Martian. In the song, Marvin wants to be friends with everyone and says he's a nice guy. However, when someone makes fun of his awkward-looking helmet, he gets angered. He then sings about his plan to fulfill destroying Earth and is seen moving his laser to destroy Earth. This was also the first appearance of Marvin's martian dog, K-9, who was seen in Marvin's lab with dog parts, after Marvin mentioned he makes puppies in his lab; and the Instant Martians, who help him with the party.
- " My name's Marvin, I'm a foreign exchange student."
In Reunion, Marvin appears in a flashback going to Daffy's high school. He is shown to not have had his helmet, due to having a long, thick line of blonde hair sticking out of the top of his head. He is shown to have been friends with Pete Puma and still is in the present. It may also be noted that he had a dislike of Daffy because when Daffy said he wanted to sit with Pete and Marvin, they both had moved away. In the present time, Marvin was seen at the reunion along with Pete, and tells Daffy and Pete that he has been plotting to destroy earth due to high school being a hard time for him. He seems to still hold an unreasoned grudge against Daffy (if he ever did) due to yelling at Daffy when he tells him that he was a player for a famous football team, while he had told another person at the reunion that he had been the coach of the team. He also appeared briefly in the Merrie Melodie, Cock of the Walk, where he is seen inside a UFO that Foghorn Leghorn is laying and singing on, because he caught them.
- " B, B-E P-O-L-I-T-E!"
- —Be Polite
In Double Date, he sings a song about being polite along with Mac and Tosh. In the song, he states that he will shoot anyone who isn't polite with his laser pistol and "vaporise" them. He demonstrates acts of politeness with the Instant Martians.
- " Wait, so this whole time he said you were taking singing lessons, you could have been bowling with u--"
- —To Bowl or Not to Bowl
He later appeared in To Bowl or Not to Bowl on Daffy's bowling team. He would (along with Pete and Porky) make Daffy feel jealous by supporting Bugs more than him.
- " You're drunk with power!"
- —Sunday Night Slice
Marvin then appears in Sunday Night Slice, where he works for Bugs' new pizza restaurant as a cook. He is later seen locked into a closet by Bugs and Speedy along with Daffy and Pete after being considered "bad service". He is later seen at the end of the episode working as a delivery man for Speedy at Pizzariba along with Daffy and Pete.
He appears in Muh-Muh-Muh-Murder, where he makes a cameo at Daffy's birthday party.
Marvin plays very little part in this season, until the finale, Super Rabbit.
- 102. Members Only (debut/Merrie Melodies)
- 106. Reunion
- 112. Double Date (Merrie Melodies)
- 113. To Bowl or Not to Bowl
- 117. Sunday Night Slice
- 125. Muh-Muh-Muh-Murder (cameo)
- 126. Point Laser Point (cameo in Merrie Melodies)
- 201. Bobcats on Three (cameo & Merrie Melodies)
- 202. You've Got Hate Mail (cameo)
- 210. A Christmas Carol (speaking cameo)
- 217. Gribbler's Quest (cameo)
- 226. Super Rabbit
- His bowling technique is to bowl and then shoot at the pins with his laser pistol.
- Marvin the Martian appeared with a green suit and a gold helmet and skirt in the earlier cartoons.
- In the episode "Reunion", Marvin has blonde hair, making his hair color blonde, but in the Merrie Melodie, I'm a Martian, he has no hair.
- In Season 2 Merrie Melodies, he has the same design as he has in Season 1 (with the exception of a yellow outline).