public static void Execute()
{
var mercenary = new Mercenary();
var citizen = new Citizen();
var firstNpc = new Npc(mercenary);
var secondNpc = new Npc(citizen);
Console.WriteLine("First NPC");
firstNpc.Communicate();
firstNpc.Threaten();
Console.WriteLine("Second NPC");
secondNpc.Communicate();
secondNpc.Threaten();
}