You play as a man who, for an unknown reason, is stranded on a floating grey platform in the middle of a featureless black void. An unseen 'Voice' demands that you take part in an arduous mental and physical trial known as 'Kurushi'.
Giant cubes stomp from the far end of the Stage toward you. You must use your 'mark' to trigger the destruction of each cube, one by one, before they roll off the edge of the Stage, and before they crush you. Succeed, and you'll open your mind to possibilities you never thought possible. Fail, and the universe will never be created. Perhaps.
It was successful enough to garner a couple sequels that never left Japan and Europe: I.Q. Final on the PlayStation, and I.Q. Remix+ on the PlayStation 2. A Compilation Rerelease for the PlayStation Portable, I.Q. Mania, was Japan-only.
- And I Must Scream: If you fail, it appears that you will fall for a very long time.
- Bizarre Puzzle Game: There's nothing in the world but a man and a lot of cubes. And you as that man have to capture all of the cubes to avoid being "avalanched" off the stage into the eternal black void. Why is all of this happening? Who knows.
- Death Cry Echo: Fall into the void, and your character will yell as they fall forever.
- Flawless Victory: Completing a level without errors in the correct number of steps earns you a PERRRRRRRRRRFECT from the Voice. Completing a level in fewer steps earns you an EEEEEEEEEXCELLENT, and a 'True Genius!' bonus. This is the only way to add rows to the stage. If, on the other hand, you do some miss some blocks, a counter will increment and you may lose one or more rows. You soon learn to do everything humanly possible to always get perfects.
- Fun with Acronyms: Intelligent Qube. The opening FMV in the first game even spells the name out with the correct spelling before going back to change it.
- Large Ham: The way the announcer belts out PERRRRRRRRFECT and EEEEEEEEXCELLENT.
- Level Editor: The game allows you put your own stages together to play.
- Mind Screw: It's not really explained what's happening in the game at all. The ending shows the player's character being returned to their normal life, be it in a town, or the army, or wherever, with the Voice sharing some words of encouragement on your victory over the trials of Kurushi. Some endings end with the caption 'The Beginning of the Universe'. If you fail, you fall off the Stage into oblivion, and the universe... simply isn't created.
- Nintendo Hard: It is extremely easy to fall behind beyond recovery after one or two bad rounds.
- Nothing Is Scarier: The game takes place in a completely featureless void with nothing but the cubes, your footsteps and the Voice. Without the music, it's very eerie.
- Pyrrhic Victory: By the time the last set of blocks appears, it is quite possible that the stage will be so short that few meaningful moves can be made. The only way to survive is to get run over by each wave of blocks, then quickly outrun the collapsing stage. By the time all the blocks have gone, the player can still win the level by being left standing on a stage consisting of a single row of blocks.
- Rank Inflation: Your "IQ" can go up to 999.
- Scoring Points: You earn ordinary points, and you're also rated on your 'IQ'
- Sinister Geometry: The only other visible object beside yourself in this game is an endless torrent of unstoppable giant stomping cubes.
- Soundtrack Dissonance: It's a game where you dodge falling cubes in the middle of a black void. For some reason, this is worthy of a soaring orchestral soundtrack that sounds like it came from some high-budget adventure movie.
- Spiritual Successor: Although they're really completely unrelated, the Practical Intelligence Quotient (PQ) series is considered by many to be the Spiritual Successor to Intelligent Qube, due to being a sort of test, clean graphics, no plot, and a 'meta person' as the main character.
- Trapped in Another World: The blackness.
- True Final Boss: Kurushi Tektonics.
- The Voice: The... Voice.
- Unstable Equilibrium: Your performance on the puzzles is heavily dependent on how many rows of playing field you have to work with. A large playing field affords the player more time to think as the cubes come rolling down; conversely, one that is too short may not even allow the player enough space to execute all of the moves required for a PERFECT. As you make mistakes, rows of the playing field start falling off, and thus you are prone to making even more mistakes. This spiral continues until you don't even have enough space for the next set of blocks to appear, which will result in being thrown off the stage to your death.
- Xtreme Kool Letterz: Kurushi Tektonics.