His mind, the mental world he calls Basic Braining, is fully explored during his class early in Psychonauts. He is one of that game's three main antagonists, the other two being the mental version of his father and his right-hand Dr. Caligosto Loboto.
Coach Oleander is first seen in the intro cinematic, delivering his open monologue to the campers around a fire. He is responsible for writing the pamphlet that inspired Razputin to run away from the circus for Whispering Rock. He is asleep for a large portion of the game, and can be heard grumbling in his sleep from the intercoms around the camp.
It is revealed that Oleander has a plot to take over the world with tanks controlled by the brains of psychics. Oleander worked with Loboto to capture the children of the camp and extract their brains.
Oleander also had Loboto put an implant into Linda, who mutated and became the Hulking Lungfish of Lake Oblongata, and the Lungfish's mind to turn into the technicolor metropolis known as Lungfishopolis wherein a projection of Oleander into Linda's mind has apparently taken over all of Lungfishopolis via a radio tower (which could be a representation of the implant) and must be defeated. The projection is known as "Kochamara", a superhero to the Lungfish, dressed head-to-toe in a blue and orange suit. Kochamara's body and voice are similar enough to the Coach, and after beating him, he claims he "no longer needs this freaky toad" and that he has "the brain of a little girl" in his lab strong enough to power an army of Psychoblaster Death Tanks.
Nearing the end of the game, Ford Cruller (outfitted with some Psitanium to keep his mind in check) blows a handful of the sneezing power into the Coach's face, leading to his brain being removed. Said brain makes its way into a Psychoblaster Death Tank, and blasts Raz's party unconscious, leaving only Raz to fight. After the tank is destroyed, Raz also sneezes his brain out. His brain uses Telekinesis to throw itself into the tank with the Coach's brain, leading to the final level of Psychonauts, the Meat Circus.
As a child, Morceau loved rabbits, and had a field full of rabbit hutches. He took a particular shine to a small rabbit in one of his hutches, and brought it out to play with it. However, he was the son of a butcher, who apparently disapproved of his son's preferences. Morceau's father told him animals were good for nothing but food, and emphasized this by taking the rabbit Morceau was playing with, and killing it right in front of him. This experience proved to be incredibly traumatic for Morceau, and has haunted him for years. When he was rejected from the military due to not being tall enough, Morceau's already scarred mental state was damaged further, driving him to devise a plan for global domination. He claims he is a former soldier, but was in reality never allowed into the Army, Navy, or Air Force because of his height. To reinforce this falsehood, he puts a fabricated Memory Vault titled "Oleander's Pride" in his mind where children can easily reach it.
Main Article: Coach Oleander's Basic Braining
Oleander's mind is a battlefield, where he trains the campers. His warzone of a mind is full of bombs, land mines, and cannons. When Razputin's and Morceau's minds are mixed together, Razputin's childhood memories of the circus where he grew up mixed with Morceau's memories of his father's butcher shop, creating the Meat Circus. Oleander reverts to his childhood state, thus creating a giant version of his father.
- Shield: Used it in the fight against the other camp staff. When the player obtains Shield in Lungfishopolis, it is stated that it was stolen from Kochamara, meaning it might have been Oleander's power.
- Marksmanship: His Psi Blast color is green.
- He can't swim because of his stumpy legs, and in Rhombus of Ruin, is so overjoyed to receive the fish tail that allowed him to float that Sasha chose not to remove it when returning him to the ship.
- Oleander is voiced by Nick Jameson, who also provides the voices for Kochamara, Dr. Loboto and Mr. Pokeylope.
- When Oleander is confused in the beginning of the game he says, "Mr. Bun? Where you going?" which reveals his personality shown in the final level of the game.
- In Oleander's first mind vault when you find, being "Oleander's Pride", he depicts himself as much taller than he is, but in the other vault, "Oleander's Shame", he was not drafted at all solely because of his height. Both vaults, as well as both of the instances you fight him (as Kochamara, he is gigantic, and the Brain Tank is much bigger than Raz) reinforce his jealousy of tall people.
- "Morceau" is a French word that refers to a morsel of meat. It can also mean "a short literary or musical composition", which could be a subtle reference to his height.
- "Oleander" may be in reference to Nerium oleander, a common garden plant with pink flowers. It is toxic in all its parts. Ingestion of this plant can affect the gastrointestinal system, the heart, and the central nervous system.