However, mice don't need to wait for a map to unlock items, and they can't get cheese with it.
On some maps, mice will need to co-operate to get the egg to avoid death (Balance Maps), or build things in more difficult to reach places, just to reach the egg (Building Maps). Players often give up their chance of getting first place in favor of getting the egg (Racing Maps).
Mice can collect eggs by touching them and getting back to the hole.
After touching an egg, the counter at the lower right corner will show a +1. If there are at least 4 mice, and you got the egg and then went back to the hole, the counter will increase.