Assignment Four: Stratagus/Wargus

Email any questions to

Xavier Otero Keil -

Joseph Siefers -

Kristen Gardner -





            To install Wargus running on the Stratagus engine download our custom installer here. Then simply run it and it will put shortcuts to the game on your desktop as well as your start menu. Do not change the install location because that will cause problems with your game. It installs by default to C:\Program Files\Wargus the installer by default does not allow you to change this and you should not attempt to.




            Your assignment is to define a new AI player in Wargus. Your AI should be fit to battle three strategies: (1) land-attack, (2) soldier’s rush and (3) knight’s rush. Your performance against these AI’s will determine seeding for the tournament of AI’s created by your classmates. You can use the custom_script.lua in the data.wargus\scripts\ai directory to define your AI. Custom_script.lua uses a similar design as the existing scripts. The script is divided into two parts: a main and end section. The main body consists of a list of API (i.e., rules) and is traversed only once. The rules in the main body are executed sequentially. To assure that an AI player will continue running when all rules in the main body have been executed, an end loop is implemented. The main body should be used to define your actual strategy (e.g., decisions on the building order, acquiring appropriate technologies and combat), the end loop should be used to initiate continuous attacks on the enemy.  See the example scripts for help with formatting and syntax. Also the API has a listing of all unit, building, and research types available. Keep in mind that this scripting language only allows for some very simple rules. Basically you define build order and when you should attack and that is it. You have no direct control of the attacks or placement of structures or anything like that. Also a good thing to keep in mind is that you also do not control the casting of spells. If you research spells Stratagus will decide when to cast them for you. I highly recommend doing this because Stratagus is highly effective at spell casting.


                Good things to know:

1.       You do not need to control the building of farms done automatically

2.       You do not need to control the collection of resources also done automatically Just use the AI set collect to set the ratio of resources you would like. I prefer 50% gold 50% wood for early game then switch to more gold in late game

3.       You do not need to rebuild buildings that are destroyed, that is done automatically.

4.       Wargus is basically Warcraft 2 so if you can find a guide on the internet for Warcraft 2 you are good to go.


Test your AI

                Once you have finished your AI, you can test it against other strategies. Start a single player game and select the desired scenario (map/strategy). By default the small map is selected. In this scenario your custom script will battle the land-attack strategy. This is not a very hard strategy to beat. It is balanced in the sense that it focuses equally on defense, offense and research. The knights-rush map is a larger map and the knight’s rush strategy employed by the opponent AI, focuses on early technological advancement. When strong units are available, it will attack with large groups of soldiers. The soldiers-rush map, uses the same map as used in the first scenario, but now your opponent AI will be defined by the soldier’s rush. Before starting the game, you must set the game type to ‘Machine vs Machine’ This will enable a game between AI players. You can speed up experiments by increasing the game speed in the options menu or you can run the fast forward mode where graphics are partially turned off, resulting in fast experiments. To do this press enter while a game is being played, and then type 'ffw ', e.g., ffw 20000 will fast forward the game to game cycle 20000. To fast forward through an entire game simply type ffw 99999999999999999999999999999999999 or whatever other arbitrary value you feel like. You can also change the scripts that you will face by going into the editor from the main menu and selecting the map you want to play on. Then open the map editor menu and select player properties. There you can choose which scripts will run each of the players.


The Competition


                The Wargus competition will be single elimination bracket based tournament seeded by your performance against the example scripts. Each battle will consist of 8 separate games. After much research into why there are large advantages for different scripts depending on maps I found several flaws in the Stragatus Machine vs Machine system. The system is full of inefficiencies that are dependent on the map. Basically the path finding gets really screwed up depending on the surrounding terrain. And since the scripting language does not let you do anything other than basically specify build order this can cause a distinct advantage for one starting point. There is also some odd handling of attacking forces that results in the higher player number getting higher priority for their attacker’s path finding. We have designed a fair map that gets around these issues that will be used for the tournament. There are 4 starting locations on it and basically you play from each of them giving everyone a fair chance to win. On this map if you play the same script against itself it is so fair that sometimes it will tie by running out of resources and there being no victor. However if this does not occur the score is always 4 to 4 wins. And if you play one script against an inferior one the stronger one always wins. Like soldiers rush vs knights rush the soldiers always win. Also the bottom right has about the same win percentage as all the other starting locations unlike before when starting there was almost a guarantee of victory.


Another side note: For the competition you will be restricted to playing as humans. This actually works in your favor since it is easier to write the script without detecting your race. However the real reason for it is that orcs for unknown reasons cause problems with Wargus and give the player using them an unfair advantage. For this reason you will not be allowed to select your race. Also orcs want to kill all humans!! and I am not down for that. 


Hints: the competition map has huge amounts of resources and is very large. Also there is never a direct path to your enemy there are many obstacles in the way. Also there is no water in any of the maps where you will be tested. The maps you will be tested on are very different from the maps that come with the game. If you want you can create your own map that is similar to this vague description in the editor and test on that.


One more side note: Depending on my ability to get this working reliably we may have an Insane Final Battle where all teams are on a small map and have to battle it out. Probably not though since having this many players causes hard to define difficulties. Try it yourself if you don’t believe me. 


PS I will not release the tournament or the test maps to you until you have turned in your final script. 


You will need to turn in your scripts the night before the due date. There are three parts to this assignment:

  1. Script (custom_script.lua)- Once your script is done, send it to us. [80%]
  2. Writeup - A write up of the ideas you used in creating your strategy. Please include in the writeup some text explaining what you have tried to achieve with your AI, but also explain what prevented you from implementing your original idea. By now, you probably experienced for yourself the limitations of the Stratagus AI. Please include a description of what you think is definitely necessary to implement sophisticated AI in a RTS game. [10%]
  3. Presentation - A 1-3 slide power point presentation giving the basics of your script design. [10%]