Spin Fighters were metal top toys from the 1990s. When you bought a standard set you got two (so they could fight each other) and they came in two colors, black and gold. On the top of the tops (yes!) were printed with characters from TV shows or cartoon characters. Some hits were the Power Rangers and WWF(E) wrestlers. If you didn’t guess, the black top usually stood for the bad guy and the gold top was for the good guy.
To play with your Fighter you used a top launcher. It would wind the tops and release them for you. You could do that on any reasonably flat surface or in the Spin Fighters Battle Bowl. In the end, the last top standing, wins. For a top toy, the Spin Fighters had a good concept and a pretty good run, but by the end of 1996, production had pretty much ended.
I am pretty sure if they had come up with a line of their own fighters instead of co-branding them, they could have launched a short run and now forgotten animated series based on the Spin Fighters. Beyblade would later do something similar. But I guess if they had not used the other properties, they might not have had the popularity they had. It is hard to know what might have been, I guess that makes it a great “what if” for the world’s historians to puzzle over for generations.