Best way to really get into a fortress is time, trickle in, know the lay out and target the most valuable area that is the most precious.
- First it would be idle observers, watchers to stay a few nights maybe even volunteer for things like guard duty, working in areas to use existing skill sets. That way they learn the people, the layout and key vulnerabilities. Every fortress has an achillies heel, even ones that are insurmountable.
- Second, the cold, its indescriminate and dangerous. What happens when a self crafted detonation occurs crippling the heating system - ie pouring sand into the generator oil lines, or glue, or rigging them to go runaway engine which means eventually they blow / burn out. While in the ensuing chaos of the power / heating going down along with the discovery of sabotage. Panic is sure to set in.
- Third, with the attention diverted inwards and panic gripping them the spare / supplies go missing only as a large force arrives in the brisk cold morning knowing full well that the night was hard on everyone there. One to make a demand, to hand over the shelter to their rule and lastly wait and watch as desperation tears the community apart.
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Villain - Caster Mann.
Short dark hair, with burns to the right of his face. A black military issue heating rig which pales in comparison to the others. His eyes are a dark hazel colour and although he looks handsome, its clear he has motivations. Intelligent, ruthless and charismatic Casters motivations are about unity, either by forceful co-ersion, desperation and outright example making. Two settlements he has control over and its not through tyranny either. Caster was a man who once believed in the good of people until desperation caused those he trusted to betray him, leave him for dead after failing to set him alight. He hunted down those who betrayed him, making examples out of their suffering that never again would people be divided and if they worked as a whole.
After murdering the leader of his second settlement and appointing himself a leader, the once slum shanty town changed to one of more fixed efficiency and design. Yes there was opposition to his methods and they were either sent into the cold, reasoned with or eventually joined his cause. Caster Mann is motivated by ensuring all surviving settlements are under his control, the main reason being that individual ownership never works. Out in the field, his own scavvers are equipped to handle the danger zones, rigged vehicles are used as an armoured train. One for the payment like a tariff of earnings, the other to resupply with just enough for the next train to top them up. This in turn means that any settlement thinking of leaving, or rebelling can deal with the cold and like wise the cold is merciless just like him.
His signature way of making an example of someone is to take them out into the cold and use a sprinkler system of water which is hot enough to avoid freezing, but on contact with the human skin cools and starts to freeze. Most end up freezing to death, others end up encased in ice and left as a grim example of why never to cross him. Its common that along the routes leading to his settments are the frozen oblisks and faces in ice staring at those who pass with lipless smiles of death. A warning to those and a deterrant to others.