5-star game
Newgrounds Rumble is a fighting game à la Smash Bros. It includes an all-star Newgrounds cast, tons of modes and most important, a free-for-all gameplay with collectable power-ups that gives you the feeling of a platform game plus the intensity of a fighting game. Survival and Story mode are addictive but my favorite is the Challenge mode where you try to win matches under different preset circumstances.
Even the details are perfect : I love how they included stats via the option-data menu ; it makes the game more interesting and add depth. The menus and music theme are untouchables. I also like "the deposit" which is like a store where you can buy rewards with the gold you've earned by completing different modes.
I'd add more of these unlockables (like alternate costumes?), longer scenarios in the story mode and maybe a universal ranking system so that players could compete with each other, trying to beat their scores.
To make it short, I'd buy it if it was a commercial game. I hope there'll be a sequel.