Bug Tunnel Defense

Take a look at this unusual cellular world, everything here is very much like a school exercise book, but it is not. As in our world, there are often conflicts, because the invaders and defenders have always been, are and will be. As the invaders, here is an army of beetles, who want to get into the secret tunnel, where they will be given full authority over this world. Protect the tunnel, using defensive guns of different types.