In the episode, Read 'em and Weep, the credits state that Cro-Marmot was voiced by Dean MacDonald. However, he does not appear at all in the episode. But if he was unfrozen, there is a possibility he will be voiced by him. This is most likely a joke by the creators.
Not counting injuries that are debatable depending on if the character died or not, Cro-Marmot is the only character to have a debatable injury (in Wipe Out!, when The Mole rams a surfing trophy into his ice block).
If you choose Cro-Marmot in the Vision-O-Rama feature in the Third Strike DVD, the movie theater's screen will be covered with ice as the Spin Fun Knowin' Ya episode is being played.
It is unknown how he does things like drive or throw snowballs, since he never moves.
Of all the characters, he has the longest space between his debut episode and his first death.
Since Cro-Marmot's hair is in a form of a bang, a hairstyle that obscures the eyes, it is unknown whether his eyes are the same style of Pac-Man eyes as most of the cast or not, which is similar to how The Mole's mouth and Handy's paw shape are unknown.
Cro-Marmot has never had an episode where he starred alone (excluding irregular episodes). He has co-starred with Giggles and Lumpy. In irregular episodes he has also co-starred with Giggles (again), Mime, and Petunia.
He co-stars with Giggles more than the other characters.
He, Flaky, Mime, and Splendid are the only characters who don't co-star with Lumpy the most. (Not counting Lammy and Mr. Pickels since they have only co-starred with each other as duo characters)
He is one of the few characters who star in only one TV episode. The others are Cuddles and Petunia.
Giggles, Petunia, and Lumpy appear in both of Cro-Marmot's regular starring roles. Lumpy dies in both episodes while Petunia and Giggles only die in one.
Cro-Marmot survived in all of his TV starring roles, along with Mime and Pop.
In the TV series, the only episodes that he doesn't appear in are "Four on the Floor", "Marooned Five", "Deep Six", and "Nine Lives".
Cro-Marmot is a featuring character in A Change of Heart, despite only appearing in one shot.
Cro-Marmot is one of the four characters who survive three consecutive segments in the TV episodes. This happens in "Seventh Heaven" (A Change of Heart, A Hole Lotta Love, and Mime to Five. The others are Pop, Lumpy, and The Mole.
Seventh Heaven is also the only TV segment to have Cro-Marmot appear in all three episodes.
He last appeared in By The Seat Of Your Pants, this makes him the one character who hasn't appeared in another episode the longest.
He is the only character to not appear in season 4 at the moment.
He, Mr. Pickels, and Lammy are the only characters to survive all of their regular starring roles. (However, Cro-Marmot dies in the irregular episode Dino-Sore Days)
Kills and deaths
Most of Cro-Marmot's deaths involve heat, explosions, and disasters.
So far, Cro-Marmot's only confirmed deaths in a regular episode were in From Hero to Eternity and Class Act, where he and several other characters were sent into a pit of lava and died in an explosion respectively.
Cro-Marmot is the fifteenth character to die in the TV series, the nineteenth or twentieth in the Internet series, and has never died in the shorts.
He is (Debatably) one of the three characters who have killed Lumpy more than the number of times Lumpy has killed him back. The other two characters are The Mole and Splendid.
He is one of the few characters who have never posthumously killed another character. The others are Russell, Splendid, and Lammy.
He has never died a gory death in a regular episode.
He is one of few characters who have killed Lifty and Shifty a different number of times. The others are Lumpy and Toothy.
He is also one of the only character to kill Lifty but never Shifty.
He is one of the few characters who have never died from any form of breathing problem like drowning, suffocation, smoke inhalation, or being strangled. The others are Flippy/Fliqpy, Splendid, Mr. Pickels, and Lammy.
He is one of the three characters to survive in every episode in which he kills another character. The other characters are Lammy and Mr. Pickels.
Giggles is the only character to be killed by Cro-Marmot alone.
He and Splendid are the only characters who have never been intentionally killed by another main character.
He and Petunia are the only characters who are not duo characters not to star without co starring with another character in a regular episode.
Cro-Marmot is one of two characters to regularly be seen with human-like hair. The other character is Disco Bear.
Cro-Marmot is one of the few characters who have never been the last character to die in one of their starring roles. The others are Mime, Lammy, and Mr. Pickels.
Cro-Marmot, Russell and Mime are the only characters (other then Lammy and Mr. Pickels) without secret information from the "Collect Them All" section, as he and Mime only appeared in the Second Serving and Third Strike DVDs.
Cro-Marmot is one of the few characters whose name is not a real word. The others are Lifty, Flippy, Lammy, and Mr. Pickels.
Cro-Marmot is one of four main characters whose first appearance, first death and first kill took place in different episodes. The other three are Flaky, Petunia and Handy.
He is one of the few characters who do not have a season 3-4 starring pop-up. The others are Mime, Flaky, and Giggles.