Ballistae can't open anytying in SS. Also in SS Mangonels are Tier 3 siege weapons like Trebuchets, not Tier 2 (unlike the Teutonics expansion). I'm on from my phone, i'll make my faction and NI choices on Sunday. I don't like spies being allowed to open doors when loading is allowed. What is to stop me from making 2 then loading untill the doors swing open and i get to assault?