Once upon a time, Rare created a happy little squirrel named Conker. Conker, it seems, was to be the star of "Conker's Day Out", yet another Rareware platformer. In this proposed game, the intrepid Conker found himself lost and far from home, and had to search for the right way back to his squirrely domicile.
Nintendo and Rare realized, however, that Yet Another Cutesy Character Platformer was probably not the way to go on a system that already had a nasty stigma of being "just for kids." Thus, Conker's Day Out, planned for a 1999/2000 release (Rare is never very good about release dates anyway) was quietly shelved*, and underwent a process of significant revision.
Conker's Bad Fur Day was developed by Rareware and published by Nintendo. The game was released in the US for the Nintendo 64 on March 6, 2001. (The European version was released on April 6, and there was no Japanese release.) The box cover and cart label are simple, with "Conker's" scribbled in red at the top and "BAD FUR DAY" in blocky text over a black background. Conker (holding a beer) and Berri are leaning against the logo.
As of this noding, CBFD is one of the most common N64 games, as it was somewhat overproduced, on top of being released late in the N64's life. Thus, it's as cheap as dirt; don't pay more than $10 for the game MIB, and don't pay more than a couple dollars for the cart alone. N64 emulation is still spotty, so any attempts to emulate this game will generally require a pretty beefy computer.
Conker, after a long night at the local pub, the Cock and Plucker, has found himself...well...he's not quite sure, but he's sure it's not home. Stuck far from home (being chased by weasels who plan to use him as a table leg), Conker needs to find his way back, and, along the way, make a lot of money, help whoever he has to to get by, and keep Berri from dumping him for standing her up.
Conker's Bad Fur Day is the antithesis of games like Banjo-Kazooie. It's rude, it's violent, and it's...well...the game the ESRB was thinking of when they created the "Mature" rating. (There's even an extra note on the front of the box that says, "ADVISORY: THIS GAME IS NOT FOR ANYONE UNDER AGE 17.")
CBFD is certainly only for adults, if not actually mature in the traditional sense of the word. Whether it's the generally gratuitous violence (even minor attacks send spurts of blood flying, as in Mortal Kombat) or excessive profanity (everything but f--- is uncensored), or having to battle a giant singing poo, the game earns its rating.
Unlike certain lame attempts at "adult" humor, CBFD is really, really funny. The dialogue is perfectly delivered; Conker is delivered with the perfect balance of cuteness and dementia, Zer Professor is suitable insane, and the minor characters all have a sort of low-brow British accent that suits the game perfectly.
If you watch carefully, you will probably spot quite a few movie references in CBFD. The opening scene is almost identical to the opening scene of A Clockwork Orange, for example, and the game references the Matrix, The Wizard of Oz, Jaws, and many others.
The big problem with the game, sadly, is that the gameplay itself is really pretty inane. Conker spends most of his time falling off of things or climbing ropes, and most of the challenge is due to the terrible, terrible camera. Even a skilled player will spend lots of time running into giant blades that seemed further away than they actually were.
Why would you want to play this game? Besides the incongruity of its existence (it was the first M-rated game Nintendo ever published, as well as a truly adult game on a pretty kid-oriented system), it's just hilarious. This is one of the funniest games since The Secret of Monkey Island.
Why might you want to take a pass? The game, in between the funny parts (which, to the game's credit, means that most of the game is fun), isn't much fun. You'll spend lots of time falling from great heights, or climbing the same damn three ropes to get that bundle of cash. Even the various odd minigames and weapons can't eliminate the intermittant tedium.
Conker's Bad Fur Day isn't for everyone, but as long as you aren't too young to get the jokes or easily frustrated, this is one of the N64 games to have.
* - All evidence of the cutesy Conker was not eliminated. Rare also released Conker's Pocket Tales, a mediocre Game Boy platformer showing the nice Conker, and nice Conker was a character in the (utterly forgettable) Diddy Kong Racing. According to Rare, however, Conker's Pocket Tales and Diddy Kong Racing show the young, still-innocent Conker, before he grew up to become the profanity-spewing squirrel of CBFD. Oh well. (Thanks to Servo5678 on the heads-up about Diddy Kong Racing.)
Sources: GameFAQs, Servo5678, Sasha Gabba Hey!/J. Totale, a good memory
Sasha Gabba Hey!/J. Totale sez: J. Totale says Interestingly, when the game was advertised on TV here [in Australia] the word "poo" was bleeped out, yet the phrase "eat my scat you little twat" was present in its entirety.