MUSCLE men (or "Millions of Unusually Small Creatures Lurking Everywhere") was first produced in Japan. Some of the characters were based on a zany Japanese comic (in fact, there is a cartoon show about it on television nowadays featuring some of the same characters) and toyline featuring robots that changed into lighters. The toyline was imported to the US and marketed by Mattel.
The actual toys were small, pink, hard rubber figures of various different wrestlers/creatures and they were available in at least three different kinds of packages: ten figures stuffed in a clear plastic garbage can; four figures in a small blister pack, or something like twenty figures in a large box.
The US toy commercials featured a nostalgia-type old B&W horror theme with the MUSCLE men invading various places around the world. Later on, a wrestling ring was released and MUSCLE men started to come in a variety of different fruit colors. A line with women wrestlers was also release ("CUTIES").