How-to: Add a background script to your mod

[Arbitrary Crusader]

I've have did what the instruction say but I'll get CTD at the starting screen.

[Killerbee]

Scripts causing CTDs when starting up your game ?

[HouseOfHam]

Uncomment the end_monitor line before your code, then it should work. But anyhow, it looks like everything you're doing should only happen when you first start a campaign and thus belongs in the campaign script (before the advance_advice_thread line there) rather than in the background script.

[Fireward77]

You see, I would like to make it a background script which starts after the 10th turn, so can you show me how to do that HouseOfHam? And I also would like to when all this happens to have greek_cities (Me) have to destroy or outlast parthia, armenia and pontus to win a short campaign, is that possible?

[HouseOfHam]

- The background script always starts at turn 0. If you want to have something happen on a particular turn, use a monitor like this:

monitor_event FactionTurnStart I_TurnNumber = 10 ; or 9, since turn numbers start with 0
      and FactionIsLocal
      and FactionType greek_cities
      ;and FactionLeaderTrai
  ; all that other code

  terminate_monitor
end_monitor

- Win conditions are configured via desc_win_conditions.txt (same folder as descr_strat.txt)

ps: You should also add some checks to prevent the monitor from getting triggered again in case the player saves the game on turn 10 and continues later.

[Fireward77]

Well I ment a Show_me Script , sorry for the confusion. well here is my updated script, I wish it would be simpler though.
Oh yea, what do I have to put to put text in the spoiler box on the forums if you know how and would be willing to tell me.

script
; Anything following a semicolon is a comment.
; Remove the adviser portrait from screen.
select_ui_element advisor_dismiss_button
simulate_mouse_click lclick_up
monitor_event FactionTurnStart I_TurnNumber = 10 ; or 9, since turn numbers start with 0
and FactionIsLocal
and FactionType greek_cities
;and FactionLeaderTrai
; all that other code
terminate_monitor
end_monitor
; Wait for it to go away.
while I_AdvisorVisible
end_while
;suspend_unscripted_advice true
; Open the adviser message bubble automatically whenever advance_advice_thread is called.
; I recommend using this method instead of the select_ui_element + simulate_mouse_click approach.
; Do NOT mix both methods, though, or the advisor will show and then immediately close before
; you get a chance to read the text.
declare_show_me
; Very useful for debugging - uncomment to use
console_command toggle_perfect_spy
; Handle saved game reloads
monitor_event GameReloaded TrueCondition
 
end_monitor
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;;; This is where to put your own code
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
console_command control greek_cities
console_command capture_settlement "Phraaspa"
console_command capture_settlement "Sparta"
console_command kill_character "Flavius Julius"
console_command kill_character "Hekhemmut"
console_command kill_character "Khnumhoptep"
console_command kill_character "Antiochus"
console_command kill_character "Aristarchus"
console_command kill_character "Demetrius"
console_command kill_character "Hanno"
console_command kill_character "Kiya"
console_command kill_character "Burrhus"
console_command kill_character "Theages"
console_command kill_character "Theodekles"
console_command kill_character "Theophanes"
console_command kill_character "Annibas"
console_command kill_character "Brennus"
console_command kill_character "Gisgo"
console_command kill_character "Eporedorix"
console_command kill_character "Vindex"
console_command kill_character "Arminius"
console_command kill_character "Ariogaisus"
console_command kill_character "Hariulfus"
console_command kill_character "Barrivendos"
console_command kill_character "Belenus"
console_command kill_character "Cynfawr"
console_command kill_character "Artaxias"
console_command kill_character "Rusa"
console_command kill_character "Zyraxes"
console_command kill_character "Vezina"
console_command kill_character "Kleomenes of Sparta"
console_command kill_character "Dionysios of Sparta"
console_command kill_character "Antigonos of Sparta"
console_command kill_character "Eumenes of Sparta"
console_command kill_character "Memnon of Sparta"
console_command kill_character "Muttines"
console_command kill_character "Syphax"
console_command kill_character "Zipoetes"
console_command kill_character "Partatua"
console_command kill_character "Viriathus"
console_command kill_character "Caraunios"
console_command kill_character "Matugenus"
console_command kill_character "Lucius Julius"
console_command kill_character "Quintus Julius"
console_command kill_character "Vibius Julius"
console_command kill_character "Sextus Antio"
console_command kill_character "Decius Curtius"
console_command kill_character "Oppius Clausus"
console_command kill_character "Aulus Brutus"
console_command kill_character "Marcus Attius"
console_command kill_character "Luca Antonius"
console_command kill_character "Caius Flaminius"
console_command kill_character "Cornelius Scipio"
console_command kill_character "Julianus Scipio"
console_command kill_character "Quintus Scipio"
console_command kill_character "Quintus Caecus"
console_command kill_character "Aulus Ovidius"
console_command kill_character "Aulus Volesus"
console_command kill_character "Flavius Nepos"
console_command kill_character "Servius Maxentius"
console_command kill_character "Antigonos"
console_command kill_character "Gyras"
console_command kill_character "Arsaces"
console_command kill_character "Ardumanish"
console_command kill_character "Mithradates"
console_command kill_character "Pharnaces"
console_command kill_character "Tiberius Brutus"
console_command kill_character "Amulus Brutus"
console_command kill_character "Decius Maxentius"
console_command kill_character "Marcus Maxentius"
spawn_army
faction parthia
character Xerxes, named character, age 30, , x 209, y 61 
unit east infantry soldiers 100 exp 5 armour 0 weapon_lvl 0
unit east infantry soldiers 100 exp 4 armour 0 weapon_lvl 0
unit east infantry soldiers 100 exp 5 armour 0 weapon_lvl 0
unit east infantry soldiers 100 exp 4 armour 0 weapon_lvl 0
unit merc arab cavalry soldiers 100 exp 3 armour 0 weapon_lvl 0
unit east heavy cataphract soldiers 50 exp 7 armour 0 weapon_lvl 0
unit east persian cavalry soldiers 50 exp 7 armour 0 weapon_lvl 0
unit east camel cataphract soldiers 50 exp 7 armour 0 weapon_lvl 0
unit east heavy cataphract soldiers 20 exp 7 armour 0 weapon_lvl 0
unit east persian cavalry soldiers 20 exp 7 armour 0 weapon_lvl 0
unit east camel cataphract soldiers 20 exp 7 armour 0 weapon_lvl 0
unit parthia huvaka soldiers 20 exp 7 armour 0 weapon_lvl 0
unit east hillmen soldiers 100 exp 0 armour 0 weapon_lvl 0
unit east archer soldiers 100 exp 7 armour 0 weapon_lvl 0
unit east archer soldiers 100 exp 7 armour 0 weapon_lvl 0
unit east archer soldiers 100 exp 7 armour 0 weapon_lvl 0
unit east elephant soldiers 38 exp 7 armour 0 weapon_lvl 0
end
spawn_army
faction pontus
character Rhadamsades, named character, age 30, , x 112, y 65 
unit east hillmen soldiers 150 exp 5 armour 0 weapon_lvl 0
unit east generals cavalry early soldiers 20 exp 5 armour 1 weapon_lvl 0
unit east infantry soldiers 100 exp 4 armour 0 weapon_lvl 0
unit east archer soldiers 100 exp 4 armour 0 weapon_lvl 0
unit merc eastern infantry soldiers 100 exp 3 armour 0 weapon_lvl 0
unit east cappodocian cavalry soldiers 100 exp 3 armour 0 weapon_lvl 0
unit east cappodocian cavalry soldiers 100 exp 3 armour 0 weapon_lvl 0
unit east scythed chariot soldiers 100 exp 3 armour 0 weapon_lvl 0
unit east scythed chariot soldiers 100 exp 3 armour 0 weapon_lvl 0
unit east chariot archer soldiers 100 exp 3 armour 0 weapon_lvl 0
unit east chariot archer soldiers 100 exp 3 armour 0 weapon_lvl 0
end
spawn_army
faction greek_cities
character Leonidas of_Sparta, named character, age 30, , x 200, y 60
unit greek general's guard cavalry4 soldiers 100 exp 9 armour 3 weapon_lvl 3
unit greek hoplite spartan soldiers 50 exp 9 armour 3 weapon_lvl 3
unit greek hoplite spartan soldiers 50 exp 9 armour 3 weapon_lvl 3
unit greek hoplite spartan soldiers 50 exp 9 armour 3 weapon_lvl 3
unit greek hoplite spartan soldiers 50 exp 9 armour 3 weapon_lvl 3
unit merc thracian soldiers 50 exp 9 armour 3 weapon_lvl 3
unit merc thracian soldiers 50 exp 9 armour 3 weapon_lvl 3
unit merc sarmatian cavalry soldiers 50 exp 9 armour 3 weapon_lvl 3
unit merc sarmatian cavalry soldiers 50 exp 9 armour 3 weapon_lvl 3
unit merc greek hoplites soldiers 50 exp 9 armour 3 weapon_lvl 3
unit merc greek hoplites soldiers 50 exp 9 armour 3 weapon_lvl 3
unit merc barbarian infantry soldiers 50 exp 9 armour 3 weapon_lvl 3
end
console_command move_character "Leonidas of_Sparta" x 209 y 61
console_command invulnerable_general "Leonidas of_Sparta"
console_command diplomatic_stance seleucid parthia Atwar
console_command diplomatic_stance seleucid armenia Atwar
console_command diplomatic_stance seleucid pontus Atwar
console_command diplomatic_stance greek_cities parthia Atwar
console_command diplomatic_stance parthia armenia Allied
console_command diplomatic_stance parthia pontus Allied
console_command diplomatic_stance armenia pontus Allied
console_command diplomatic_stance greek_cities armenia Atwar
console_command diplomatic_stance greek_cities armenia Atwar
console_command diplomatic_stance greek_cities seleucid Allied
 
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;;; End of your code
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
; Spin forever - Do not let the script terminate or any monitors you have set up will immediately get thrown away.
while I_TurnNumber < 99999
suspend_unscripted_advice true
end_monitor
end_while
end_script

[Aradan]

Use [ code][/code ] tags, makes things easier to read.

[HouseOfHam]

[spoiler][code]
your code here
[/code][/spoiler]

so that will look like:

Spoiler Alert, click show to read: 

your code here

- I wouldn't recommend specifying the exact number of soldiers in a unit, since that number does not automatically adjust when you change the unit size.
- Any characters names you use in the spawn army commands must be valid names from descr_names.txt, etc. Double-check that.
- According to the docs, the valid diplomatic stances allied/neutral/war

Spoiler Alert, click show to read: 

script

; Anything following a semicolon is a comment.

; Since you don't have anything happenening during battles, you can add this line to optimize things a bit.
suspend_during_battle on

; Remove the adviser portrait from screen.
select_ui_element advisor_dismiss_button
simulate_mouse_click lclick_up

; Wait for it to go away.
while I_AdvisorVisible
end_while

suspend_unscripted_advice true

; Open the adviser message bubble automatically whenever advance_advice_thread is called.
; I recommend using this method instead of the select_ui_element + simulate_mouse_click approach.
; Do NOT mix both methods, though, or the advisor will show and then immediately close before
; you get a chance to read the text.
declare_show_me

; Very useful for debugging - uncomment to use
console_command toggle_perfect_spy

; Handle saved game reloads
monitor_event GameReloaded TrueCondition
	terminate_script
end_monitor

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;;; This is where to put your own code
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
monitor_event FactionTurnStart I_TurnNumber = 10			; or 9, since turn numbers start with 0
			and FactionIsLocal
			and FactionType greek_cities
			
	console_command capture_settlement "Phraaspa"
	console_command capture_settlement "Sparta"
	console_command kill_character "Flavius Julius"
	console_command kill_character "Hekhemmut"
	console_command kill_character "Khnumhoptep"
	console_command kill_character "Antiochus"
	console_command kill_character "Aristarchus"
	console_command kill_character "Demetrius"
	console_command kill_character "Hanno"
	console_command kill_character "Kiya"
	console_command kill_character "Burrhus"
	console_command kill_character "Theages"
	console_command kill_character "Theodekles"
	console_command kill_character "Theophanes"
	console_command kill_character "Annibas"
	console_command kill_character "Brennus"
	console_command kill_character "Gisgo"
	console_command kill_character "Eporedorix"
	console_command kill_character "Vindex"
	console_command kill_character "Arminius"
	console_command kill_character "Ariogaisus"
	console_command kill_character "Hariulfus"
	console_command kill_character "Barrivendos"
	console_command kill_character "Belenus"
	console_command kill_character "Cynfawr"
	console_command kill_character "Artaxias"
	console_command kill_character "Rusa"
	console_command kill_character "Zyraxes"
	console_command kill_character "Vezina"
	console_command kill_character "Kleomenes of Sparta"
	console_command kill_character "Dionysios of Sparta"
	console_command kill_character "Antigonos of Sparta"
	console_command kill_character "Eumenes of Sparta"
	console_command kill_character "Memnon of Sparta"
	console_command kill_character "Muttines"
	console_command kill_character "Syphax"
	console_command kill_character "Zipoetes"
	console_command kill_character "Partatua"
	console_command kill_character "Viriathus"
	console_command kill_character "Caraunios"
	console_command kill_character "Matugenus"
	console_command kill_character "Lucius Julius"
	console_command kill_character "Quintus Julius"
	console_command kill_character "Vibius Julius"
	console_command kill_character "Sextus Antio"
	console_command kill_character "Decius Curtius"
	console_command kill_character "Oppius Clausus"
	console_command kill_character "Aulus Brutus"
	console_command kill_character "Marcus Attius"
	console_command kill_character "Luca Antonius"
	console_command kill_character "Caius Flaminius"
	console_command kill_character "Cornelius Scipio"
	console_command kill_character "Julianus Scipio"
	console_command kill_character "Quintus Scipio"
	console_command kill_character "Quintus Caecus"
	console_command kill_character "Aulus Ovidius"
	console_command kill_character "Aulus Volesus"
	console_command kill_character "Flavius Nepos"
	console_command kill_character "Servius Maxentius"
	console_command kill_character "Antigonos"
	console_command kill_character "Gyras"
	console_command kill_character "Arsaces"
	console_command kill_character "Ardumanish"
	console_command kill_character "Mithradates"
	console_command kill_character "Pharnaces"
	console_command kill_character "Tiberius Brutus"
	console_command kill_character "Amulus Brutus"
	console_command kill_character "Decius Maxentius"
	console_command kill_character "Marcus Maxentius"
	
	spawn_army
	faction parthia
		character Xerxes, named character, age 30, , x 209, y 61
		unit east infantry soldiers 100 exp 5 armour 0 weapon_lvl 0
		unit east infantry soldiers 100 exp 4 armour 0 weapon_lvl 0
		unit east infantry soldiers 100 exp 5 armour 0 weapon_lvl 0
		unit east infantry soldiers 100 exp 4 armour 0 weapon_lvl 0
		unit merc arab cavalry soldiers 100 exp 3 armour 0 weapon_lvl 0
		unit east heavy cataphract soldiers 50 exp 7 armour 0 weapon_lvl 0
		unit east persian cavalry soldiers 50 exp 7 armour 0 weapon_lvl 0
		unit east camel cataphract soldiers 50 exp 7 armour 0 weapon_lvl 0
		unit east heavy cataphract soldiers 20 exp 7 armour 0 weapon_lvl 0
		unit east persian cavalry soldiers 20 exp 7 armour 0 weapon_lvl 0
		unit east camel cataphract soldiers 20 exp 7 armour 0 weapon_lvl 0
		unit parthia huvaka soldiers 20 exp 7 armour 0 weapon_lvl 0
		unit east hillmen soldiers 100 exp 0 armour 0 weapon_lvl 0
		unit east archer soldiers 100 exp 7 armour 0 weapon_lvl 0
		unit east archer soldiers 100 exp 7 armour 0 weapon_lvl 0
		unit east archer soldiers 100 exp 7 armour 0 weapon_lvl 0
		unit east elephant soldiers 38 exp 7 armour 0 weapon_lvl 0
	end
	
	spawn_army
	faction pontus
		character Rhadamsades, named character, age 30, , x 112, y 65
		unit east hillmen soldiers 150 exp 5 armour 0 weapon_lvl 0
		unit east generals cavalry early soldiers 20 exp 5 armour 1 weapon_lvl 0
		unit east infantry soldiers 100 exp 4 armour 0 weapon_lvl 0
		unit east archer soldiers 100 exp 4 armour 0 weapon_lvl 0
		unit merc eastern infantry soldiers 100 exp 3 armour 0 weapon_lvl 0
		unit east cappodocian cavalry soldiers 100 exp 3 armour 0 weapon_lvl 0
		unit east cappodocian cavalry soldiers 100 exp 3 armour 0 weapon_lvl 0
		unit east scythed chariot soldiers 100 exp 3 armour 0 weapon_lvl 0
		unit east scythed chariot soldiers 100 exp 3 armour 0 weapon_lvl 0
		unit east chariot archer soldiers 100 exp 3 armour 0 weapon_lvl 0
		unit east chariot archer soldiers 100 exp 3 armour 0 weapon_lvl 0
	end
	
	spawn_army
	faction greek_cities
		character Leonidas of_Sparta, named character, age 30, , x 200, y 60
		unit greek general's guard cavalry4 soldiers 100 exp 9 armour 3 weapon_lvl 3
		unit greek hoplite spartan soldiers 50 exp 9 armour 3 weapon_lvl 3
		unit greek hoplite spartan soldiers 50 exp 9 armour 3 weapon_lvl 3
		unit greek hoplite spartan soldiers 50 exp 9 armour 3 weapon_lvl 3
		unit greek hoplite spartan soldiers 50 exp 9 armour 3 weapon_lvl 3
		unit merc thracian soldiers 50 exp 9 armour 3 weapon_lvl 3
		unit merc thracian soldiers 50 exp 9 armour 3 weapon_lvl 3
		unit merc sarmatian cavalry soldiers 50 exp 9 armour 3 weapon_lvl 3
		unit merc sarmatian cavalry soldiers 50 exp 9 armour 3 weapon_lvl 3
		unit merc greek hoplites soldiers 50 exp 9 armour 3 weapon_lvl 3
		unit merc greek hoplites soldiers 50 exp 9 armour 3 weapon_lvl 3
		unit merc barbarian infantry soldiers 50 exp 9 armour 3 weapon_lvl 3
	end
	
	console_command move_character "Leonidas of_Sparta" x 209 y 61
	console_command invulnerable_general "Leonidas of_Sparta"
	
	console_command diplomatic_stance seleucid parthia war
	console_command diplomatic_stance seleucid armenia war
	console_command diplomatic_stance seleucid pontus war
	console_command diplomatic_stance greek_cities parthia war
	console_command diplomatic_stance parthia armenia allied
	console_command diplomatic_stance parthia pontus allied
	console_command diplomatic_stance armenia pontus allied
	console_command diplomatic_stance greek_cities armenia war
	console_command diplomatic_stance greek_cities armenia war
	console_command diplomatic_stance greek_cities seleucid allied
	
	terminate_monitor
end_monitor

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;;; End of your code
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

; Spin forever - Do not let the script terminate or any monitors you have set up will immediately get thrown away.
while I_TurnNumber < 99999
suspend_unscripted_advice true
end_monitor
end_while
end_script

[Fireward77]

Ill try it, and if it don't work ill post back ASAP.

[Starvin Marvin]

Hi i have followed you tutorial basically just copied and pasted it all, just to see if i could get the advisor then adding my own code, but every time i try and load rome up it is not responding, i have undone everything i have copied and pasted, then it works fine. so i followed the tutorial again, and now it won't respond.

[HouseOfHam]

Seeing how you're the first one of more than 1100 people who have viewed this thread to have this problem, I'd say you did something wrong.

[Agisilaos]

wonderful work you have done!!! thanks H.O.H.

[HouseOfHam]

Updated 1st post - added a way to terminate the background script. See the script code for details and explanation.

[Killerbee]

Great tutorial HouseofHam ! I have one question though : Is it possible to have a BuildingIsLocal Building = 'building' condition ? So that there must be a building present to make the script appear ?

This is my script :

Spoiler Alert, click show to read: 

script

declare_show_me

;console_command toggle_perfect_spy

monitor_event ScrollAdviceRequested ScrollAdviceRequested end_game_scroll
    terminate_script
end_monitor

; Handle saved game reloads
monitor_event GameReloaded TrueCondition
  terminate_script
end_monitor

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;;; Zeus code
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

monitor_event BuildingIsLocal Building = muster_field
spawn_army
faction greek_cities
character Polydoros of Sparta, general, command 0, influence 0, management 0, subterfuge 0, age 20, x 155, y 61
unit greek general's guard cavalry early, soldiers 20 exp 9 armour 1 weapon_lvl 0
unit greek peltast, soldiers 20 exp 9 armour 1 weapon_lvl 0
end

;;;; End

while I_TurnNumber < 99999
  suspend_unscripted_advice true
end_while
end_monitor
end_script

Another thing : Every time i clicked on a settlement or character , the advisor showed up saying 'Script is activated' .. How can i disable this ? And when you click on it , it goes away immediatly .. I know you mentioned this , but i don't see what i'm doing wrong ..

[HouseOfHam]

Nope, no such condition, unfortunately.

There are a couple problems with that code:

1. No event is being monitored.

monitor_event <EventName> <1stCondition>   ; or TrueCondition if none
          [and AdditionalConditions]
  ; commands
end_monitor

An event is something like FactionTurnStart. BuildingIsLocal, if such a thing existed, would be a condition.

Btw, in RTW conditions, if something is Local doesn't mean that it's of the same culture as the settlement. Rather, it belongs to the player faction.

For example, this will deduct 100 gold from the player's treasury for every settlement they own:

monitor_event SettlementTurnStart SettlementIsLocal
    console_command add_money -100
end_monitor

2. The while I_TurnNumber < 99999 loop must be just before the end_script tag, outside the monitor_event...end_monitor block. This is why advisor is popping up every time you click on a settlement.

I'm not exactly sure what the goal of your monitor is, but since you're spawning that army for a specific faction and settlement, you could try something like this...

declare_counter spartaMusterField  ; initialized to 0 by default

; Set variable to 1 when player constructs muster_field in Sparta
monitor_event BuildingCompleted SettlementBuildingFinished = muster_field
          and SettlementIsLocal
          and I_LocaFaction greek_cities
          and SettlementName Sparta
  set_counter spartaMusterField 1
end_monitor

; Only spawn when that variable is set
monitor_event SettlementTurnStart SettlementIsLocal
          and I_LocaFaction greek_cities
          and SettlementName Sparta
          and I_CompareCounter spartaMusterField = 1
  console_command kill_character "Polydoros of Sparta"   ; to avoid character cloning CTD
  spawn_army
    faction greek_cities
    character Polydoros of Sparta, general, age 20, x 155, y 61
    unit greek general's guard cavalry early, soldiers 20 exp 9 armour 1 weapon_lvl 0
    unit greek peltast, soldiers 20 exp 9 armour 1 weapon_lvl 0
  end
  terminate_monitor ; so it doesn't spawn on every turn
end_monitor

[Killerbee]

Alright , many thx ! My goal was to spawn an army when you builded a ceratin building (not the muster field ofcourse , but that's easy to test )

Great ! All problems solved and it works ! I owe you big time A +rep would do the trick

[Killerbee]

Hi , sorry for double post and "reviving" this topic , but i thought it would be better to do this than make a whole enw thread .. I have a little "problem" .. fact is ,t hat my script does what i ask , but it generates an error when i exit the game .. This is my script :

Spoiler Alert, click show to read: 

if I_SettlementOwner Sparta = greek_cities

set_counter SettlementOwner Sparta 1
end_if

if I_CompareCounter SettlementOwner Sparta = 1

  console_command kill_character "Polydoros of Sparta"   ; to avoid character cloning CTD
  spawn_army
    faction greek_cities
    character Polydoros of Sparta, general, age 20, x 155, y 61
    unit greek general's guard cavalry early, soldiers 20 exp 9 armour 1 weapon_lvl 0
    unit greek peltast, soldiers 20 exp 9 armour 1 weapon_lvl 0
  end
end_if

while I_TurnNumber < 99999
  suspend_unscripted_advice true
end_while
end_script

error said somthing like : undefined number at line 54 ..

This is line 54 :

if I_CompareCounter SettlementOwner Sparta = 1

But still the army gets spawned ..

[makanyane]

I_SettlementOwner Sparta = greek_cities
is a condition and is legitimate code

set_counter SettlementOwner Sparta 1

requires a declared counter of "SettlementOwner Sparta" which I don't think would work because of the space in the counter name - think the error message is maybe about it trying to use 'Sparta' as a number

calling the counter name something similar to the condition might be convenient but if its confusing you try making it something completely different eg:

declare_counter SOS

if I_SettlementOwner Sparta = greek_cities
set_counter SOS 1
end_if

if I_CompareCounter SOS = 1

  console_command kill_character "Polydoros of Sparta"   ; to avoid character cloning CTD
  spawn_army
    faction greek_cities
    character Polydoros of Sparta, general, age 20, x 155, y 61
    unit greek general's guard cavalry early, soldiers 20 exp 9 armour 1 weapon_lvl 0
    unit greek peltast, soldiers 20 exp 9 armour 1 weapon_lvl 0
  end
end_if

obviously needs start and end script bits as well

fact that its 'working' might be similar to some non-valid code I had recently which HoH pointed out was just defaulting 'true'

EDIT: if that is all the counter is doing though, you shouldn't need it

if I_SettlementOwner Sparta = greek_cities
  console_command kill_character "Polydoros of Sparta"   ; to avoid character cloning CTD
  spawn_army
    faction greek_cities
    character Polydoros of Sparta, general, age 20, x 155, y 61
    unit greek general's guard cavalry early, soldiers 20 exp 9 armour 1 weapon_lvl 0
    unit greek peltast, soldiers 20 exp 9 armour 1 weapon_lvl 0
  end
end_if

would do same thing

[Killerbee]

Yep , i know , i made that script before , but i want to make something else (more complicated) .. I wanted to do a certain thing , that would occur for instance only 3% each turn .. So your chance is 1/33 each turn that the script would generate .. But , i wanted that , if you have multiple settlements (2 to be precise :p) , the chance would increase .. So then i thought about the Counter .. i was thinking something like :

Spoiler Alert, click show to read: 

script

if I_SettlementOwner Sparta = greek_cities

set_counter SettlementOwner_Sparta 1
end_if

if I_CompareCounter SettlementOwner_Sparta = 1
   and RandomPercent < 5

  console_command kill_character "Polydoros of Sparta"   ; to avoid character cloning CTD
  spawn_army
    faction greek_cities
    character Polydoros of Sparta, general, age 20, x 155, y 61
    unit greek general's guard cavalry early, soldiers 20 exp 9 armour 1 weapon_lvl 0
    unit greek peltast, soldiers 20 exp 9 armour 1 weapon_lvl 0
  end
end_if

if I_SettlementOwner Athens = greek_cities

inc_counter SettlementOwner_Sparta 1
end_if

If I_CompareCouner SettlementOwner_Sparta = 2
   and RandomPercent < 10

  console_command kill_character "Polydoros of Sparta"   ; to avoid character cloning CTD
  spawn_army
    faction greek_cities
    character Polydoros of Sparta, general, age 20, x 155, y 61
    unit greek general's guard cavalry early, soldiers 20 exp 9 armour 1 weapon_lvl 0
    unit greek peltast, soldiers 20 exp 9 armour 1 weapon_lvl 0
  end
end_if


while I_TurnNumber < 99999
  suspend_unscripted_advice true
end_while
end_script

Note how the percentage should increase when i capture Athens ..

EDIT : it worked .. i used following script :

Spoiler Alert, click show to read: 

script

if I_SettlementOwner Sparta = greek_cities

set_counter SettlementOwner_Sparta 1
end_if

if I_CompareCounter SettlementOwner_Sparta = 1
   and RandomPercent < 5

  console_command kill_character "Polydoros of Sparta"   ; to avoid character cloning CTD
  spawn_army
    faction greek_cities
    character Polydoros of Sparta, general, age 20, x 155, y 61
    unit greek general's guard cavalry early, soldiers 20 exp 9 armour 1 weapon_lvl 0
    unit greek peltast, soldiers 20 exp 9 armour 1 weapon_lvl 0
  end
end_if

if I_SettlementOwner Thermon = greek_cities

inc_counter SettlementOwner_Sparta 1
end_if

if I_CompareCounter SettlementOwner_Sparta = 2
   and RandomPercent < 100

  console_command kill_character "Polydoros of Sparta"   ; to avoid character cloning CTD
  spawn_army
    faction greek_cities
    character Polydoros of Sparta, general, age 20, x 155, y 61
    unit greek general's guard cavalry early, soldiers 20 exp 9 armour 1 weapon_lvl 0
    unit greek peltast, soldiers 20 exp 9 armour 1 weapon_lvl 0
  end
end_if

while I_TurnNumber < 99999
  suspend_unscripted_advice true
end_while
end_script

[HouseOfHam]

Looks like you didn't read my note about what happens if you try to use wait in a monitor_event block.