Underdog?
Unicorn.
Underdog
hades
kazoo
you mean the letter U? UnderDog
Underdog is a cartoon character.
Linus from Charlie Brown
Scooby-Doo was originally , and only , a cartoon . There are a number of comic books with the titular character .
Arnold from "Hey Arnold". the show used to be on nickolodeon
Andrew Hartley and Frank Stea of ATGradio.com
Alfred from 'Batman'