A. B. C-more is a mischievous green male humanoid elf creature with gremlin-like ears who hosts the Fairy Fly-Pad game A.B.C-more's Elf-Abet Challenge in the Sesame Street video, Elmo's Alphabet Challenge.
Claiming to be the greatest alphabet expert in the world, the elf entraps Elmo, Telly and Abby in his game, where they must defeat him in order to leave. Despite his self-proclaimed title, he is constantly one-upped by the players due to his lack of alphabet knowledge (such as thinking "cat" starts with I) and also misunderstandings (seeking an H word, he misses a hamburger, claiming "meat sandwich" doesn't start with H). Not being able to cope with losing, he constantly changes the format of his game, only to be defeated because of his hubris. A running gag during the video has him getting harmed by a cactus in different games, getting to a point where he meekly states he has no idea why he keeps putting them in his games.
When the gang finally wins the game, he sulks over his failures, but is cheered up when they tell him his game was fun after all. He sees the world outside of his game and poofs himself into the real world (appearing now in Muppet form). He is initially hesitant, wishing to be back where letters are everywhere, when he learns that everything everywhere is made of letters. He joins them in a game of basketball.