|Family:||Blue Oak (grandson), Daisy Oak (granddaughter)|
|Class:||Professor, former Trainer, former Champion|
|First Appearance:||Chapter 002: VS Bulbasaur|
Professor Oak (Japanese: オーキド博士 Dr. Ōkido) is a support character in Pokemon Adventures. He has appeared in the Red, Green & Blue, Gold, Silver & Crystal, FireRed & LeafGreen, and Emerald arcs. He is the creator of the Pokedex and appears to act as the handler to the Pokédex owners.
Professor Oak is based on an NPC of the exact same name, as such, he sports the same outfit. He wears a red, short-sleeved polo shirt, brown pants, black shoes, and a lab coat.
Red, Green, & Blue arc
Oak makes his debut as he enters his lab and a kid dressed in red is already there, rummaging through his stuff. He shouts at him calling him a thief. The surprised boy, as he tries to explain himself, accidentally releases all of the Pokémon in his lab. Oak then demands that the boy re-capture all of the Pokémon he let loose. Though he did as ordered, some of the Pokémon escaped the lab. The boy introduced himself as Red and Oak introduced himself back. Though still untrusting of Red, Oak followed him as they recaptured all the Pokémon eventually winding up in Viridian City. The last Pokémon they had to find was a Bulbasaur, that ran into the city's abandoned gym. They entered behind it. Oak tried to calm the Bulbasaur down only to get Tackled. Red tried to calm it down and with better results. Oak noticed how the Bulbasaur warmed up to him. Suddenly, he and Red were attacked by a wild Machoke. Oak then passed out. He awoke after Red and Bulbasaur defeated Machoke with Solarbeam. He asked how he knew about Solarbeam and Red replied that he just thought that plant (the bulb) would need sunlight. Oak then heard Red out about why he went to his lab. Oak then explained that he would need to find his own strength. He then gave Red a Pokédex and Bulbasaur then parted ways.
He later appears in Viridian Forest observing Red and his grandson, Blue beginning their rivalry. He was the one who revealed to Red the existence of Team Rocket. After Red's Bulbasaur evolves into Ivysaur, Oak tells Red that someone stole a Squirtle from his lab.
He was later captured by Team Rocket in order to complete the Mewtwo experiment after their top scientist, Blaine had defected. After Adventures}} was defeated by Red and Blue, they rescued Oak from captivity and helped him to escape.
During the Pokemon League, Professor Oak entered the tournament under the alias 'Dr. O'. After going up into the semi-finals, he was matched up against Green. He eventually gains the upper hand during the match due to his experience as a trainer and taking advantage of Green's ornithophobia. After Green is defeated in battle, Oak reveals that he knew Green stole the Squirtle from his lab years after she was kidnapped by a bird Pokemon and a mysterious man. He forgives Green for stealing the Squirtle and gives her a Pokedex. Professor Oak forfeits the tournament for Red and Blue to settle their rivalry. His forfeit also meant that Green is pushed into third place of the tournament.