Program: 2065
Project: 2065
Buggy source:
private void createNPC(String[] args,Player player){
  String text="String_Node_Str";
  ArrayList<String> texts=new ArrayList<String>();
  if (args.length >= 3) {
    int i=0;
    for (    String s : args) {
      if (i == 2 && !s.isEmpty() && !s.equals("String_Node_Str"))       text+=s;
      if (i > 2 && !s.isEmpty() && !s.equals("String_Node_Str"))       text+="String_Node_Str" + s;
      i+=1;
    }
    texts.add(text);
  }
  if (args[1].length() > 16) {
    player.sendMessage(ChatColor.RED + "String_Node_Str");
    return;
  }
  if (PropertyPool.getNPCAmountPerPlayer(player.getName()) < PropertyPool.getMaxNPCsPerPlayer() || PropertyPool.settings.getInt("String_Node_Str") == 0) {
    int UID=plugin.handler.spawnNPC(args[1],player.getLocation(),player.getName());
    PropertyPool.saveNPCAmountPerPlayer(player.getName(),PropertyPool.getNPCAmountPerPlayer(player.getName()) + 1);
    plugin.handler.setNPCText(UID,texts);
    plugin.handler.setOwner(UID,player.getName());
    player.sendMessage(ChatColor.GREEN + "String_Node_Str" + StringUtils.yellowify(args[1],ChatColor.GREEN)+ "String_Node_Str");
    if (EconomyHandler.useEconomy()) {
      int paid=EconomyHandler.pay(Operation.BASIC_NPC_CREATE,player);
      if (paid > 0)       player.sendMessage(MessageUtils.getPaidMessage(Operation.BASIC_NPC_CREATE,paid,args[1],"String_Node_Str",false));
    }
    NPCManager.NPCSelected.put(player.getName(),UID);
    player.sendMessage(ChatColor.GREEN + "String_Node_Str" + StringUtils.yellowify(args[1],ChatColor.GREEN)+ "String_Node_Str"+ StringUtils.yellowify("String_Node_Str" + UID,ChatColor.GREEN)+ "String_Node_Str");
  }
 else {
    player.sendMessage(ChatColor.GREEN + "String_Node_Str" + StringUtils.yellowify("String_Node_Str" + PropertyPool.getMaxNPCsPerPlayer(),ChatColor.GREEN)+ "String_Node_Str");
  }
}

Fixed version (ground truth):
private void createNPC(String[] args,Player player){
  String text="String_Node_Str";
  ArrayList<String> texts=new ArrayList<String>();
  if (args.length >= 3) {
    int i=0;
    for (    String s : args) {
      if (i == 2 && !s.isEmpty() && !s.equals("String_Node_Str"))       text+=s;
      if (i > 2 && !s.isEmpty() && !s.equals("String_Node_Str"))       text+="String_Node_Str" + s;
      i+=1;
    }
    texts.add(text);
  }
  if (args[1].length() > 16) {
    player.sendMessage(ChatColor.RED + "String_Node_Str");
    return;
  }
  if (PropertyPool.getNPCAmountPerPlayer(player.getName()) < PropertyPool.getMaxNPCsPerPlayer() || PropertyPool.settings.getInt("String_Node_Str") == 0) {
    int UID=plugin.handler.spawnNPC(args[1],player.getLocation(),player.getName());
    PropertyPool.saveNPCAmountPerPlayer(player.getName(),PropertyPool.getNPCAmountPerPlayer(player.getName()) + 1);
    plugin.handler.setNPCText(UID,texts);
    plugin.handler.setOwner(UID,player.getName());
    player.sendMessage(ChatColor.GREEN + "String_Node_Str" + StringUtils.yellowify(args[1])+ "String_Node_Str");
    if (EconomyHandler.useEconomy()) {
      int paid=EconomyHandler.pay(Operation.BASIC_NPC_CREATE,player);
      if (paid > 0)       player.sendMessage(MessageUtils.getPaidMessage(Operation.BASIC_NPC_CREATE,paid,args[1],"String_Node_Str",false));
    }
    NPCManager.NPCSelected.put(player.getName(),UID);
    player.sendMessage(ChatColor.GREEN + "String_Node_Str" + StringUtils.yellowify(args[1])+ "String_Node_Str"+ StringUtils.yellowify(UID)+ "String_Node_Str");
  }
 else {
    player.sendMessage(ChatColor.GREEN + "String_Node_Str" + StringUtils.yellowify("String_Node_Str" + PropertyPool.getMaxNPCsPerPlayer())+ "String_Node_Str");
  }
}