It sounds like you're referring to (often called Smash Remix ), a notable fan-made ROM hack of the original Super Smash Bros. for the Nintendo 64. The "200" might point to something like:
To the average player, Smash Remix 200 looks like a fever dream. To programmers, it is a miracle. The N64 has only 4 MB of RAM (or 8 MB with the Expansion Pak). To fit 200 major assets, the team used: smash remix 200
Players can now change the overall game speed or use a "Remix" option to slow down time. It sounds like you're referring to (often called