Sometimes Wii owners get creative. When they can’t (or don’t) get downloadable expansions, etc., they can just make do and invent their own.
Pulling from the Capcom Unity blog about the “Monster Protector” side game:
This new side game, Monster Protector, is a fun spin on the average hunt. Instead of all four hunters slaying the beast, one hunter takes it upon himself to prevent the monster from being slain.
This side game has become popular enough that a whole site has been created to lay out all the nitty-gritties for those interested in playing along.
It sounds like there are a few side games out there, such as the somewhat opposite “Devil of the Hill”, so if you love MH3, it might be worth checking out.