0²

"A benevolent creature, 0² rarely presents any trouble in the cloud levels of Shiver Star."

- Description

0² (pronounced "Zero Squared") is the true main antagonist and final boss of Kirby 64: The Crystal Shards. Although it is not directly stated, 0² is presumed to be a reincarnated form of Zero due to the bandage on its head and appearence as a fallen angel. It resides deep within Dark Star, a gargantuan sphere of amassed Dark Matter.

Background
Rather than taking control of Pop Star, the Dark Matter infest the equally peaceful home world of the Fairies, Ripple Star. While not seen to be producing any Dark Matter, 0²'s role as final boss as well as the location being fought, suggests with the same reasons for Zero that it is the intelligence behind Dark Matter-related events. Judging from the Dark Matter invasion, it appears that 0²'s goal, whatever it plans to do with the infested planets, remains unchanged from Zero.

Since the Dark Matters' first priority on Ripple Star is the destruction of the Power Crystal in Ripple Star Palace, it is clear 0² knows the Crystal presents at least a credible threat to the plans in motion. It is seen near the end of the game that the reunited Power Crystal has the capability to purge Dark Matter from the person being infested (Queen Fairy in this case) with a beam of light and relieve them of its possession. Comparatively speaking, the Power Crystal (and its Ribbon's Shard Gun derivative) to 0² is the Love-Love Stick to Zero. Playing into the fairly clear light and dark themes the game presents, it suggests Zero, 0² and Dark Matter are weak against light from the Power Crystal at least, as well as certain positive emotions as suggested by the effects of the Love-Love Stick against Zero previously in Kirby's Dream Land 3.

Kirby 64: The Crystal Shards
Because 0² isn't even encountered until late in the game, it stays behind the scenes causing trouble through its Dark Matter minions. 0² is truly the one responsible for breaking the Power Crystal on Ripple Star and causing trouble on the different planets.

0² is a secret and optional boss that can only be faced if the player has every single Crystal Shard. Unless every shard in the game is collected, Miracle Matter serves as the "final boss". Kirby has the Shard Gun during the fight, and Ribbon uses her wings to guide Kirby around. At first, 0² is impervious to absolutely any attack. It can be stunned, however, by continuously shooting at its eye. During this process, though, it will constantly shoot exploding energy balls with decent accuracy. While it is stunned, Kirby must fly up and aim for the halo. After enough damage is done to the halo, 0² flips over revealing a long green thorn-like tail on its bottom. This is its weak spot, so Kirby has to get as much damage as he can before it flips back over and the whole cycle repeats. However, when attacking the tail, it shoots several green clouds of gas at random directions and is constantly moving, thus making it hard to aim at. Also, while stunned, it is possible to damage 0²'s wings, which will result in it moving much slower. Essentially, 0² is more susceptible to damage like this. While 0² still has wings, it will follow Kirby wherever he flies. If Kirby destroys them though, he can fly above it, and shoot its halo without having to shoot its eye first.

After blasting 0² with Crystal Shards from the Shard Gun, the monster explodes, destroying it and Dark Matter once more, ending its reign of terror on the galaxy for now.

Concept art of 0² can also be seen in the game's ending credits.

Physical Appearance
0² greatly resembles Zero and has the vision of a fallen angel. It has a bulbous white sphere as a body and a red eye. New additions include a pair of segmented wings, a halo, the eye is much larger, a bandage at the top (only visible when it flips forwards) and a tiny spike or tail on bottom. When the spike is exposed as his weak spot it extends in length, turns bright green and gains spines, making it look like a cactus.

As Kirby enters the core of Dark Star, 0² first wears an amiable visage; two black dots resembling beady eyes above a wide smile. As Kirby and Ribbon form the Crystal Shard Gun, its "mouth" opens up wide, its trademark blood-red eye is revealed, its false eyes disappear as the face melds together, and the battle initiates. This may be a reference to Gooey.

Trivia

 * During this fight, on the pause menu, the "Try Again" option is replaced with "Tough It Out!". This option has the same effect as "Continue."
 * A remix of 0²'s theme is an unlockable song in Super Smash Bros. Brawl by collecting at least 5,000 coins in coin matches.
 * 0², along with Zero, are the few characters who are shown to bleed or shed blood-tinted tears when fought - they are the two most gruesomely-depicted characters in the series.
 * The Prima strategy guide for Kirby 64: The Crystal Shards is flawed; it states that 0² is a peaceful character who appears in Stage 2 of Shiver Star. Dark Star is left out entirely.