Evolution of a Character - Mario (Smash Files 16)
All of the fighters in the original game have these two image types, from what I've found - the first being a 2D drawing that was the main style used in promotional artwork for the game, and then a different picture with their actual appearance in-game. Something to note: in the N64 picture, Mario's pants look purple. I can't quite remember whether they were actually like that in-game, but I'm leaning towards it just being an error with the picture above.
Obviously Mario was in Melee, so he received artwork again. Like every piece of character artwork from Melee, the background has a stripe of white and a block of solid color, along with a black bar along the bottom telling us the character's name (because nobody knows who Mario is already...). Mario took a huge jump in graphics over the N64, although his face in particular very closely matches the promotional artwork for Super Mario 64.
Coming into Brawl, Mario was redesigned with a much darker, duller color palette to match the the more mature tone of the game. His clothing is also even more detailed than Melee, and F.L.U.D.D. becomes one of his attacks. Coincidentally, F.L.U.D.D. is also the reason I don't often use Mario anymore - I'd much rather have an attack that does actual damage in my arsenal.
And now in the upcoming game, Mario simultaneously looks better and less detailed. You can't really pick out the individual seams in his overalls like you could with Brawl, but at the same time Mario looks so smooth that you don't really miss it. Mario also has a fireball ready in his hand this time around - he means business, people. Don't you forget that!
And of course, I'd be lax to not include an image of Mario from the upcoming 3DS game, which uses a different graphics style than the WiiU version. Mario looks as though he was taken right out of a comic book in the 3DS version, with the cel-shading and the black outline forming what is a cool look (if seeming somewhat removed from the battlefields). When I get the game I'll probably remove those outlines, though - Mario feels like a big block with it sitting there.
That's all I've really got for now. If you have any specific character you'd like to request for an evolution or a profile, just let me know and I'll get right on it. In the meantime, I must continue compiling that list of retro stages I want to battle on again....