8bit has no meaning without context, FYI. What's limited to 8 bits? The space on the drive the tiles take up? The processing power of the computer? The number of colors (which, btw, is a lot)?
Er, sorry, people using the term "8-bit" or "16-bit" to describe art is a pet peeve of mine. I'm going to make a wild guess and assume you mean that the artwork looks a lot like it would work in an 8-bit memory console. That still doesn't have a lot of meaning without context but gets us closer. So, pixel art, probably low color count. There's lots of tiles that fit that still, Tiny 16, Old School Modern, Crazy Leen's retro tiles, POP! Horror, ect. Could you give us any more info to help narrow it down? Like maybe tell us what kind of game you want to make?