A seriously funny flash cartoon that many people think is a blatant ripoff of the flash cartoon series "Happy TreeFriends". This is not true, simply because the characters talk and make jokes in RAB, whereas in Happy Tree Friends the only "humor" is pointless violence.
a retardi b is someone who thinks they are cooler than everyone else just because they know all the words to Cardi B's songs. they think they are cool but in reality they look very stupid, hence the name, "retardi b"
"ugh there maddie goes with her stupid rapping"
"i know, she thinks she's talented but shes really just making a retardi b of herself"