Doc Louis first appeared in Punch-Out!!. He is an ex-heavyweight boxing champion and Little Mac's coach. He can be seen training him throughout the Punch-Out!! series, and is the sparring opponent in Doc Louis's Punch-Out!!, a WiiWare game serving as a spinoff of the Punch-Out!! Wii game.
Doc Louis does not appear in Brawl in person, but he is mentioned in the description of Little Mac's trophy.
Doc Louis appears in Little Mac's trailer for Super Smash Bros. 4, where he is seen training him, as well as narrating the gameplay portion of the trailer as advice called out to Mac. He appears in all of Little Mac's victory poses in the game itself, briefly sparring with him and cheering him on. Occasionally when Little Mac taunts in game, Doc can be heard cheering for him. These clips change with Little Mac's size, and can even play when Little Mac is metal. A real life Doc Louis also appears in an American commercial for Super Smash Bros. for Nintendo 3DS.
He also appears as an item in Smash Tour: he boosts by 1.5x the effect of all powerups gathered in the turn his trophy is selected.
Victory pose dialogue
In all of Little Mac's victory poses, Doc is seen saying one of the following phrases:
In addition, Doc will say one of the following phrases if Little Mac is in his wireframe attire.
Doc Louis appears as a trophy in Super Smash Bros. 4.
Doc Louis reprises his appearances in Little Mac's taunts and victory poses.
In addition, he appears in the World of Light as a Master Spirit. Defeating him will unlock the gym, where Doc Louis will train up to four Primary Spirits at a time. Spirits left in the gym will steadily gain experience, even when the game is shut off.