Do you need to give credit/get permission to use these?

@ThatOneIG2013Guy both at the same time

am I seeing sms sonic sprites or sega genesis sonic sprites

Not only that but there are system limitations to play. Sonic's Edusoft didn't have many sprites during gameplay (more obvious on the Green Hill attempt) with most of the graphics being the background and usually it's just Sonic himself as the only sprite, even Sonic 1 itself didn't have a lot of objects on screen. If you got large sprites then the chances of going over the sprite limit are very high and you get sprite flicker, it also happens if you use up the scanline sprite allocation (like in Double Dragon). The other alternative to remove sprite flicker is not suitable for a Sonic type of game (using the background, a technique often used in bosses for action games but games like After Burner, Altered Beast and Golden Axe are background based). Some later Master System games that work around the sprite flicker and sprite based are also known for slowdown, again not ideal.

Adapting the style with smaller dimensions actually works in favour, saving colours for the palette of the badniks and other objects, reducing the chance of sprite flicker and yet recognisable enough.

I think it's because the Sonic's Edusoft sprites are too big for this game

Surprised they didn't go with the Sonic's Edusoft sprites, since they're literally just rips of the Genesis version with downgraded colors.

shawnik

Reminds me of the Sonic Chaos prototype.