These figures were my favorite! They came in packs of 4, packs of 10 (came in a transparent garbage can), and the big 28 box! I remember going to Toys R Us and getting a free promo poster that had every figure on it with a check box next to it. My brother bought the wrestling ring, but the pegs that held up the figures broke within a week or so.
These were a lot of fun to play with. I remember my friends and I came up with a paper and dice game based around the figures. We'd five them special power moves and attributes.
There was a NES game based on the characters, but I remember it was pretty terrible.
M.U.S.L.E. was originally based on a manga series called Kinnikuman!