Phi Brain is supposed to be about mind games and dangerous puzzles where failure may lead to death. The protagonist is a genius in puzzle solving and for that he is chosen to be part of a dangerous puzzle solving line of games. You probably noticed that I wrote the word “puzzle” many times in a short amount of words, but trust me the anime keeps mentioning it even more frequently. You know, like in YuGiOH where they mention the word “cards” every two minutes. Same thing. And it is of equal level with that show as well, despite trying to sound serious and intelligent with the word puzzle. Oh, and it’s hardly as cool as well.
The characters are standard shounen stereotypes; too irritating and dumb to get a liking for. Shallow as well since the only thing they live for is solving puzzles if they are boys or following around boys as minor support if they are girls. Yay! And haven’t we all got tired of shows where high schoolers go to school where the only thing they are doing is NOT school work? Hey guys, I know it is very important to show that they are good kids who go to school every day, but it is kinda pointless if it is just there without a purpose in the story. IT IS ABOUT SOLVING PUZZLES, NOT SHOWING SCHOOL GROUNDS! I bet they do it on purpose so they can reuse scenery footage from other shows. Or waste airtime. Or get to our nerves.
The protagonist is supposed to be super smart and we are meant to find that cool or something but in reality it is all an illusion. Remember Lelouch in Code Geass where most thought he was a great chess player? Same thing; we are only given a few glimpses of the game and then the solution is offered without ever showing us HOW HE DID IT. So looking at the hero solving a sudoku in 10 seconds without ever seeing his line of thought, means ABSOLUTELY NOTHING. If you happen to have watched Kaiji or Akagi then you know what I mean. There is absolutely no flavour or fleshing out between the characters and the way they think and feel. They are retards with nothing inside and you get bored of them very fast.
Thus the whole show has to do with puzzles as much as Naruto has to do with ninjas. NO RELATION AT ALL! Hell man, what is the point of a mystery if you are just told who the guilty guy is right away, without ever explaining WHY? And what is the point of wasting 2/3rds of each episode in irrelevant school nonsense and tired juvenile humour? 
It is all a retarded motivational show so little kids can go solve sudokus or something. Too bad it is never actually helping them to be better at solving them, so chances are they will give up fast and return to playing Counterstrike or something. As for the REALLY smart kids, I bet that watching such a show will make them dumber.
The final nail in the coffin is when the protagonist is offered a magical item that makes him even more imba in puzzle solving (without again showing us how), as if he couldn’t do it without it. Oh and his eye changes colour as well. The relations to YuGiOh and Naruto never end and thus it is clearly of the same level as them right away. Fancy but retarded. Later on they constantly try to make us feel there is a world conspiracy going on and there is this ancient power that can do a lot of stuff if you… yes, solve puzzles. They even try to make it look as if the protagonist is taken over by a dark side and the whole thing reeks of YuGiOh stereotypes and a thousand times of hearing the same words repeat again and again.
NOT GOOD AT ALL! This is what Kaiji and Liar Game watch to laugh. This is what paralyzed people watch so they can facepalm. This is what you will show to the geek boy in your class, so its scores will drop and make fun of later.
Oh, I forgot to say something about the production values, didn’t I? Ok, here you go: They are mediocre without any attempt at making the puzzles exciting. And that is all you need to know about them.
