Story
Please refer to the story in the 128-Bit page.

Characters: Crash Bandicoot/Coco Bandicoot/Crunch Bandicoot/Fake Crash/Aku Aku
Uka Uka/Emperor Velo 27^th/Dr. Cortex/N. Gin/Tiny/Dingodile/N-Trance/Polar
Nitros Oxide/Krunk/Nash/Norm/Big Norm/Geary/N. Tropy/Spyro the Dragon^TM

Generalities
CNK on the GBA plays much like its 128-bit counterpart, so before reading on, make sure you're well acquainted with that version.

The GBA is a handheld with poor 3D capabilities, so the tracks in this version are completely different. Although they are technically 3D to some extent, they are completely flat with no terrain at all. The characters themselves are sprites, whose frames have been directly ripped from the 128-bit version models. The music was completely remade except for the title song, but it is extremely annoying to find out each tune only has around 10-15 seconds before looping. Another major difference lies in the cutscenes- they're now composed of still shots from the main version's FMVs. The last downgrades are the character taunts, which aren't nearly as many as in the 128-bit version.

The basic gameplay is retained, although it lacks such features as Team Frenzy and trigger traps. Some tweaks were made in order to compensate for the GBA's smaller button count. For example, you need to let go of the acceleration button in order to slide-boost and tap it accordingly.

Only 3 game modes are accessible this time: Adventure, Arcade and Time Trial. Each mode behaves the same way as in the main version, except you don't get a Perfect bonus by getting all the Crates in Time Trial.

Controls:
Accelerate- Hold down the A button.
Brake- Hold down the B button.
Reverse- Hold the D-Pad downward.
Use weapons- Press the L button.
Jump- Press the R button.
Power Slide- Hold down R and push the D-Pad sideways.
Slide Boost- When Power Sliding, let go of the A button and tap it when the meter turns red (3 boosts per slide).

Weapons (note: get 10 Wumpa Fruits for juiced up versions and increased kart speed):
Missile: engages pursuit on the nearest opponent.
Juiced up: it tracks enemies and avoids collisions better.

Explosive Crate: a TNT crate is dropped behind. Whoever hits it will blow up in a few seconds unless that person manages to jump enough times to get the Crate off of his/her head.
Juiced up: It turns into a Nitro crate that explodes on contact.

Bowling Bomb: Roll this bomb forward or backwards (pull the left analog stick/D-Pad backwards). It will detonate once it hits someone or something, or if you decide to press the Circle button again.
Juiced up: Bigger blast radius.

Static Orb: an electrifying blue orb is left behind. Anyone who hits it will spin uncontrollably and won't be able to use weapons for a short time.
Juiced up: an electrifying pink orb is left behind and the effect lasts longer.

Ice Mine- a blue mine is dropped. Anyone who hits it will spin uncontrollably and freeze into an ice cube. The character can continue to race, but the slippery ice makes it difficult.
Juiced up: The effect lasts longer.

N. Tropy's Clock: Time temporarily slows down for everyone except for the person who uses it. The opponents will also undergo an uncontrollable spin at first.
Juiced up: The effect lasts longer.

Turbo Boost: An extra boost for the go.
Juiced up: The boost lasts longer.

Shield: A green shield appears around the character, enabling the player to suffer 1 hit point without inflicting damage. Anyone who touches the character will get bumped high into the air and the shield will disappear. It can be shot as a projectile by pressing L. Will wear off eventually.
Juiced up: The shield won't wear off with time now, and is blue-coloured.

Aku Aku/Uka Uka mask: You'll be invincible for a short time, and any contact with the opponents bump them high into the air.
Juiced up: The effect lasts longer.

Tornado Top- It sends out a tornado that automatically hits everyone in front of you, and will not be destroyed by colliding with objects or walls. When a character is hit, he'll spin high into the air by the Tornado.
Juiced up: The Tornado's hitting effect lasts longer.

Game Modes:
Adventure- The main story, and where you unlock most stuff (single player only).

Arcade- Choose a track or cup to compete against other characters (single and multiplayer).

Time Trial- Race freely through any of the available tracks to get the best time, with no opponents or power-ups (singe player only).