Brainy Smurf is one of the main characters of the cartoon adaption of The Smurfs. Throughout the series, he is portrayed as an annoying character who was supposedly meant to act out as a moralizer to the Smurfs but turns out to be a bit talkative, boastful, and somewhat of a smart aleck and spoilsport character who is more likely to blab out, much to the annoyance of everyone.
Why He Sucks
He constantly boasts on and on about his knowledge, making him a big showoff.
He talks too much. Whenever he states out something, his sentences tend to be so long that it could get on the other Smurfs' nerves, resulting in him getting thrown off the village (which serves as the running gag of the series, making him the Butt-Monkey).
He behaves like a stuck-up smart aleck who thinks he knows everything at times, which makes the season 12-16 counterpart of Thomas the Tank Engine look like a poindexter in comparison. He would blab out something that is true but could lead to trouble, and even acting like he knows better that anyone, which isn't true.
He is also considered incompetent in most episodes (especially Season 6 onward), trying to help around the village, usually resulting in anger from the others (especially Papa Smurf).
At times he acted like he was second-in-command of the village, using the excuse that he is Papa Smurf's assistant when he was actually Papa Smurf's lab assistant and apprentice, meaning he was confused. In the original comics, he never was Papa's apprentice to begin with.
Although he and Clumsy are best friends, he didn't always treat him that way (see below).
He is unlikable in some episodes, mostly the ones where he is occasionally miscast as the antagonist dozens of times whenever Gargamel or the other villains are absent from an episode, even though he's supposed to be one of the good guys.
His villainous side debuted in the cartoon adaptation of "King Smurf". He ruled the village like a tyrant and started a civil war, though he does apologize at the end and is not as worse as his later appearances. In the original comic version, he was held captive as one of King Smurf's prisoners and is not the antagonist.
He was also unlikable in the episode "Clumsy Luck", since he was responsible for all the trouble Clumsy went though (when Clumsy broke Vanity's mirror, Brainy claimed that Clumsy got bad-luck by using the cliche about people getting bad luck from breaking a mirror and even tried to quarantine him, preventing him from having fun and seeing the meteor shower. And after Clumsy escaped from his house, a mediator crushed his house, causing the other Smurfs, especially Papa Smurf when he returned from Homnibus' place, to think Clumsy got killed and made a funeral for him. Brainy is also mourning as well (although it was all his fault, making him a hypocrite). Thankfully, Clumsy returned, and much to everyone's surprise, they were happy to see him alive and well the whole time. (Brainy also got what he deserved, but he never learns anything from it).
In "Brainy's Smarty Party", he ejects the Smurflings from his party, and kicks out many of them (even Clumsy), causing the remaining Smurfs to leave.
"The Smurfy Verdict" is another example. He framed Clumsy for the disappearance of Baby Smurf, although it was his responsibility to take care of him in the first place. He doesn't even apologize for framing his best friend and claims to finish off his case instead, lacking any empathy whatsoever. Being thrown out at the end doesn't trigger his empathy side either, he just complains about "Some justice."
He was a spoilsport to Grandpa Smurf's stories in the episode "The Royal Drum".
He doesn't have a sense of humor and can't seem to take a joke, as seen in "April Smurf's Day".
He is infamous for his Quotations of Brainy Smurf series of books (beginning in Season 3), which were never adapted to the original comics.
He never changes his behavior and remains self-centered, arrogant and egotistical for the rest of the series. Like Bloo, he is the opposite of character development.
Most episode plots revolve around him causing chaos around the village and/or trying to live up to his name. His personality bares similarities to Fred Flintstone and Daffy Duck, but without the likable qualities of either.
Although the other Smurfs get annoyed by his behavior, they still love and care for him, especially Smurfette, who sometimes hates to see the other Smurfs bully him although she too despises his behavior.
He was likable in some episodes, but that's not saying much.
To be fair, the other Smurfs never give him a chance or at least tolerate him, instead they always throw him out of the village pretty much every time he talks, even though the Smurfs are supposed to be kindhearted and forgiving especially to each other, but that still does not excuse his treatment.
He always gets his comeuppance by getting thrown out of the village. Unfortunately, in the ninth season, the gag seemed to get old pretty quickly (even by late 80s standards).
After this cartoon, Brainy became less annoying and more likable in later media.