He is a giant red venomous snake with strong fangs and a long snake tongue. He has yellow eyes typical of venomous snakes.
He is sentient as humans and can talk. He also wear clothes, like a purple cylinder with a skull and a ribbon on his neck. He has eyelashes with dark blue/black make-up, he looks like similar to a Goth makeup. (there are some male variants of makeup in that subculture sometimes used by musicians of fans of the genre)
His house is serpent-head shaped, with the mouth and fangs as front porch of the door, and resembles him.
He is really selfish and narcissist.
He is individualist and lives alone, caring only about himself. He loves his appearance and loves to keep cure of himself. He loves also his shed skins, infact he does them a lot. He also did his house snake shaped and similar to him.
He is evil with everyone else, and he treats the Slugs as slaves in order to have a beautiful artigianal lavoration of his shed skins.
Even if he is not seen to use this magic, he can make his shed skins as servants and use them to protect him in fighting. He also can make magic unbreakable chains to make slaves people or animals, like happened to the Slugs. He can send the "Uncommon Cold", a cold which notices to a person a message, and then curing it with creating a magical egg.
He can use the strong venom to attack and probably also suffocating people or animals in his grips due to his large size. If he managed to catch Courage in the pursuit, he probably did these things to him. Due to his large size, he is quite slow in movements. However, he has a versatile serpentine body which can move well both in ground and water.
Big Bayou appears in his only debut episode as the main and only villain.
He lives in an african (probably) forest where he built a serpent head shaped house: he lives alone in that house. The entire forest where he lives is full of statues made by his shed skin. The "puppets" are his shed skins filled by straw to don't fall to the ground and for making them looking as statues. They are created by some Slugs , which he enslaved using his magic and creating unbreakable chains for them.
The Slugs someways manages to steal half of the page of the magical book of the snake where it was written how to send the uncommon cold, a message sent via cold. They only found the first half of the page. so they don't know how to heal a victim after sending it.
Courage listens to the message because Muriel was affected by that illness, so he is forced to go to free from slavery the Slugs. He arrives in the forest crossing a river with Muriel, and he gots scared by the Shed Skin statues once he arrives in the dark forest.
He and Muriel reach the Slugs, which are enslaved in a cave with chains. The slugs say they must defeat Big Bayou not only for freeing them but also for healing Muriel.
While these events, Big Bayou is having fun to do compliments to himself and appreciate his beauty. Then he does another shed skin to transform into statue and goes to do a bath in a small natural pool where he contemplates about himself seeing his image in the water.
Courage goes to the Big Bayou's house and manages steal his magic book using his impressionably long tongue from the "eyes" of the house which are opened windows without glass. He first takes other books useless for his plans, then he takes the magic book but only ruining the right eye-window of the house.
While Courage manages to heal the uncommon cold from Muriel, Big Bayou returns from the bath and discovers the presence of the dog and the old woman. He starts to pursue Courage, arriving in the river. Courage uses the Bayou book as a boat to cross the river, Bayou swims with his own gargantuan body.
Arrived near some shed skins statue in the river, the serpent tries to bite Courage with his poisonous fangs but had the misfortune to hit the book instead of the dog. This makes the poison of the fangs falling into water and making the Bayou statues alive as the magic book stated. However Courage reads how to order a Shed Skin minion to attack, and being the first to give the order the statues start obeying to him. Courage fastly orders to them to attack Big Bayou, the serpents tries to escape but he gets defeated by them easily.
After Courage returns to home with Muriel, the Big Bayou tries to send the uncommon cold to Eustace to have a rescue. In his message Big Bayou is seen chained and wounded, and so that was what the Shed skin servants did to him.
- Despite serpents have not eyelashes, Big Bayou has them, which are also covered with a dark male "gothish" make-up
- He has lot of personality traits in common with Narcissus, a character from Greek mythology.
- Even if he is a really strong dark magician, he's not seen using his magic in active way. His magic is only seen in his book and being done by other characters.
- He is not sure if he managed to escape after being defeated and chained by the traitors shed skin servants, but probably he did it sending the Uncommon Cold to someone.
- In the episode of Big Bayou it can be seen how the tongue of Courage can be long.
- The inner part of the serpent shaped Big Bayou's house is not seen well. It's only seen the room where the snake sleeps, but no other room. This because Courage didn't entered in it.
- Big Bayou is one of the only two snakes of the saga. Other one is Snake.
- Even if Carmen is called as a serpent, she looks like more than a serpentine sea dragon, so she shouldn't be considered properly a snake.
- Big Bayou speaks with lot of S in words, being a serpent.
- Big Bayou was one of 17 villains who were not part of the Ball of Revenge. The others were Fred, Schwick, Velvet Vic, Mondo, Mattress Demon, Jeeves Weevil, Fishsionary, Evil Empress, Bluff, King Ramses, Dr. Gerbil, Elisa and Eliza Stitch, Benton Tarantella, King of Flan, Errol Von Volkheim and Mad Dog.
- He is also a one-time character.