I need some help, please. How do you destroy the greek fire siege engins in revelations? whenever I'm defending my dens I manage the infantry an rifle men easily enough but no matter how many assassins stationed around the roofs and baricades, upgaded and manned, I haave on the road the engine gets through and destroys everything. I have crossbowmwn, riflemen, air asassins, leaders and baricades. how can I desroy the monters. Help with this please.