This oughta help. I found it in the Kid Chameleon Manuel that came with the game. (Diamond powers are used by pressing A + Start.)

Kid Chameleon
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Special Powers - Leaping Flip.
Diamond Powers - Circle of Doom (kills any enemy it touches) - requires 20 Diamonds.
- Death Snake (seeks enemies and kills them) - requires 50 Diamonds.

Iron Knight
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Special Powers - Crawl up walls and obstacles. Press the Special button rapidly.
Diamond Powers - Circle of Doom (kills any enemy it touches) - requires 20 Diamonds.
- Extra Hit Point - requires 50 Diamonds.

Red Stealth (a.k.a. Shinobi)
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Special Powers - Sword attack (Press Jump + Special to attack downwards).
Diamond Powers - Samurai Haze (slows down all enemies) - Requires 20 Diamonds.
- Death Snake (seeks enemies and kills them) - Requires 50 Diamonds.

Berzerker
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Special Powers - Charging obstacles (Press and hold the Direction Button)
Diamond Powers - Invulnerability. Requires 20 Diamonds.
- Wall of Death (disintegrates enemies/obstacles) Requires 50 Diamonds.

Maniaxe
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Special Powers - Throwing axes.
Diamond Powers - Circle of Doom (kills any enemy it touches) - requires 20 Diamonds.
- Extra Life. Requires 50 Diamonds.

Juggernaut (a.k.a. Tank)
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Special Powers - Firing skull bombs.
Diamond Powers - 5-Way Shot. Requires 5 Diamonds per shot.

Micromax (a.k.a. The Fly)
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Special Powers - Sticking to walls (press Jump + Direction Button to jump onto wall).
Diamond Powers - Mini-Snake (seeks enemies and kills them) - Requires 20 Diamonds.
- Swift Mini-Snake (faster than Mini-Snake) - Requires 50 Diamonds.

EyeClops (a.k.a. VR)
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Special Powers - Revealing unseen blocks for a short time.
Diamond Powers - Fatal Beam (hurts enemies it hits) - Requires 2 Diamonds per shot.

Skycutter
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Special Powers - Flying upside down (Press Jump + Special to flip upside down.
Press Special again to flip right-side up).

Diamond Powers - Invulnerability. Requires 20 Diamonds.
- Death Snake (seeks enemies and kills them) - Requires 50 Diamonds.

Cyclone
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Special Powers - Whirlwind flight (press Jump, then press Special rapidly).
Diamond Powers - Slashing Rain (knifes into enemies) - Requires 20 Diamonds.
- Tracking Rain (seeks foes and slashes them) - Requires 50 Diamonds.

Kid Chameleon; Regular joe. He can run, jump and that's about it.
Shinobi; Shinobi can run faster, jump higher and has a sword for killing enemies or smashing blocks.

Iron Knight; Iron Knight is very heavy, he can just break blocks by jumping on them. He can also climb walls like spidey.

Beserker; Beserker has horns on his head so when he gets running he can headbutt things like blocks or some enemies.

The Fly; the fly can't run very quick but is a small target, he can also stick to walls temporarily so he can scale verticle faces.

Cyclone; Cyclone can spin at very high speeds to enable him to fly.

Tank; this turns you into a tank which lets you shoot skulls at enemies. He can also widthstand a lot of punishment.

VR; VR lets you shoot a green ray all over the screen. While this does no damage to enemies it lets you see hidden blocks, but if you hold down A and Start together, you can use up 2 diamonds to help kill your enimie, it's like shooting them.

I can't think of any others at the moment but I hope this helps.

the suits are fly,tank,rhino,ninja,axe murderer, thats all i can remember