if you approach to mega cheese, you will disconnected

Screenshot:

This is the server's anti-hacking system. Every cheese has a fixed position on a map and the same specific area where one can obtain the cheese without the server detecting any source of hacking. However, the area where one can obtain the cheese without Transformice detecting any foul play does not increase as the cheese enlargens. Hence, if you achieve cheese outside of that specific area (when the cheese get's significantly larger), the server will think you are hacking and automatically kick you.
(Sorry that it's explained in really simple terms. I got this information from a mod around a month or so ago and can't quite recall the specific terms used).

Maybe all of you have the cheese power so the cheese is huge. now all of you are shamans and more shamans means huger cheese.

Exactly what Izu said.Shaman skills can be combined, there are some bugs where people were able to use the wing skill of the other shaman.