Description:In the quiet days, they went climbing as usual. They suddenly encountered the changing weather, and collectively strayed into the time tunnel. They came to the ice age amazingly! Living environment below 0 degrees, fierce prehistoric creatures, wild primitive people! Everything, constantly updating their mind of knowledge, in order to return to reality,We must find the time tunnel, the abnormal changes of the environment, the difficult terrain, many unknown creatures constantly attack and attack them!! What happened in the prehistoric era??