1) Hive have numbers and are far more intelligent those mindless brutes ( Mind over matter) 2) who says they cannot live on earth. who's says that they might have more advanced suits to compensat for earths gravity ( more new enemies to encounter) 3) which tower? the crow's nest is the tower of london. (https://www.google.co.uk/search?q=tower+of+london&oq=tower+of+london&aqs=chrome..69i57j69i60l3j69i61l2.3100j0j7&sourceid=chrome&es_sm=0&ie=UTF-8) plz do your research before you post ( not being mean here. just saying i have put alot of thought into this and did research to back it )