Here is an awesome little Mario flash clone that is really fun and easy to play. Here is a snippet:
"Super Mario 63 is a fan-game inspired by Nintendo's Super Mario 64. Many levels and features are based upon it and other of Nintendo's games, but a variety of them are completely original. Among them include a detailed storyline, ability to play as Luigi, a highly customizable Level Designer with sharable codes, three different FLUDD Power-ups, four different power-caps, and 64 Shine Sprites & 64 Star Coins to collect."
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