Fatal Force: Earth Assault

Just imagine that a great explosion that thundered on Tunguska in 1908, created a unique zone in Siberia. Newcomers on the Tunguska do not intend to leave. On the contrary, they are determined to capture the entire Earth. It is clear, that these humanoids are absolutely unaware of history of our planet and are completely out of date about consequences for them. Well we have to make it hot for them...