As a child of the '80's it was all Star Wars, GI Joe and Transformers. Going along with the football theme here, I loved the NFL Action Team Mate figures. Very hard to find now and most of the ones you find are damaged or missing the boxes/accessories. I remember spending hours just smashing these guys together. Like Megos, many came in both boxes or on cards. They had African American figures too, which are pretty rare today. They were about 7 or 8 inches tall I think and they had removable helmets too which was really cool.
What was really cool is each figure came with a full set of decals so you could change the numbers to whatever player you wanted.