Super Mario Crossover Nothing's Perfect. But this is damn close.
You're interview was very inspiring, and I encourage everyone to read it to see what this dude had to deal with in making tihs game.
To FlameTH's comments about jumping/movement problems: Yea, the characters are different. You want them all to be mario? I love the extra difficulty in Simon's movements, the challenge from Link's sliding, Mega Man's lack of attack options other than shooting and jumping compared to the other characters, making it feel like he BELONGS in this game, since all of his games are pretty challenging (to me at least) Bill's crazy jump style with his upgradable pea-shooter, and Samus's awesome abilities.
You really have to somewhat "practice" with the other characters to get used to them. If you're used to a game they're from though, it's easier. Mega Man fans? Easy for ya, beat this game! Castlevania? Psh, you got this. Metrod? Well, it's pretty different, but for the better! Contra? Holy crap that game is hard anyways (to me... okay?) You got dis.
All I will say is that this is probably THE best flash game I've played in a LONG time. In fact, Nintendo themselves could probably make a killing off of this if it was an established game, just by itself, no changes. It's that good.
Honestly, the only thing I can say negatively about it is that a few collisions with enemies feel a little unfair, like just barely touching a turtle's neck or head when you're JUMPING on them with freakin' Link! Jesus. How many times do I have to die like that?!
Anyways, my favorite character now is Simon. Next is between Megaman and Bill. Awesome game. If anyone doubts the abilities of Simon... Think of it this way:
Simon: Best character to get points with (high score). Throw axes at bricks EVERYWHERE, you're guaranteed over 30-40 thousand points a level or MORE. Con is that he is hard to maneuver around certain enemies. (Blooper god damn you)
Bill: Great character, haven't played with him enough, but he's great for passive kills and reaching enemies around him easily. Can shoot many blocks, maybe not as fast as Axes are from Simon, but damn fast.
Megaman: Best character to use if you're new to platform games like Mario. Honestly, he's easier to use than Mario, IMO.
Mario: Honestly, do I need to say anything?
Samus: Best for last, I honestly think Samus is the most versatile character in the game. When you get her Zero Suit fireflower form, it's like overkill for monsters, because of her linear attack line plus coverage of the area. She can aim it up and down is the best thing, plus ball form is the best thing since sliced bread.
BIG. HUGE. THUMBS UP. For this game. Good work, I hope to see more from you. I am doing challenges on this game now, just to see if I can. I have yet to beat it because I don't want to die at all with Simon. XD!