brilliant. The shifting of the whole building makes this game just that much harder. If it didn't move, then the game would be too easy just simply stack them up like you would in tetris and make it stable 5/5
Another tip. use any regular gun to snipe off any people that are out of row, but if there is a huge bunch of people let them be... then let them get to your wall and then nade them. Repeat process =D
Hehe hell dining was soo easy!!! simple... max out wall and get maxed out grenade launcher and let spam repair then just shoot grenades till they get to the wall and then spam the grenades