Extremely fun, for a _long_ time
At last, someone has accomplished what I wasn't sure was possible in a Flash fighter, while still keeping the individuality of each character: a BALANCED FIGHTING GAME! Everyone has their own strengths and weaknesses.
Well, kinda. Samurai Asshole's way overpowered. But other than him (tone down his health a little more and shorten the range on his sword, to make up for all his infinite combos both on the ground -- such as DOWN+Q, DOWN+F, Q, DOWN+Q, DOWN+F, Q, etc -- and in the air -- best one's Q, Q, F, F, Q, Q, F, F, etc), the rest of the characters are all balanced. Some are better in air, some are better on the ground, some are better at getting in there and trading blows with the opponent while others are better at hit 'n' run style...and _all_ of them are fun to play. (Well, the Charade-style character Convict can be a bit annoying at times when he morphs back into his normal form _just_ after you get a projectile item, but then that randomness is part of the fun of playing him.)
The non-character unlockables are interesting, too, especially the Orbiter and Regeneration items. Not a big fan of the Junkyard, especially against computers -- who tend to be easily trappable under the trash compactor within the first fifteen seconds or so of play -- but other than that the normal and unlockable levels are all coolness.
In case you're curious on the reasons for my scores...
Graphics: 10. The simple and yet simultaneously detailed graphics style fits the game perfectly. No further comment there.
Style: 9. It's a fighter, so I just _had_ to take off a point for the imbalance of Samurai Asshole. But hey, many professionally-made fighting games are unbalanced too, so this does a far better job than even most Capcom games. No real complaints there.
Sound: 8. The music comes from other Newgrounds submissions, although many tracks seem modified -- in a good way -- but the vocal sound effects could be kind of annoying. Guns and such were fine, but hearing Piconjo's grunts every other sword swing, and same for Samurai Asshole, was rather annoying at times -- especially if someone got an invisible double, Ninja Gaiden style, so there were _two_ Piconjos swinging and grunting. Perhaps just lowering the volume of the vocal sound effects relative to the others would be sufficient.
Violence: 10. It's a fighter. Everyone's slicing everyone to bits. Pico's death animation involves decapitation. 'Nuff said.
Interactivity: 10. It's a game. Bah.
Humor: 9. Storyline was funny at parts.
Overall: 9. This should be a 10, since my only real complaint is the annoyance of the vocal sound effects, but the overpoweredness of Samurai Asshole is still getting to me. I've played too many fighters, I s'pose; imbalance drives me insane. It's really not a fair score considering the balance of this relative even to many Capcom games (Zangief, anyone? v_V). Give yourself a 10. :P