The main additional functionality compared to other card game simulation programs is that Magic Project understands the rules of the game. Rules are human-written using a specific XML pseudo-language, giving the Magic Project game engine all the necessary information to properly simulate the card game. For card games with static rules (like No Limit Texas Hold 'Em Poker), writing the rules file is not a too difficult task. For collectible card games (CCG), we often encounter a base set of rules that describes the game and one or more specific set of rules corresponding to each card.
A card game is described by a main XML file and a set of other XML files for each card in that game. For example, in a Magic the Gathering card game, you'll have a big file named mtg.xml in the src/main/resources/tbs directory. Each implemented cards have a dedicated XML file in the src/main/resources/tbs/mtg/recycled directory. The name of the file is the name of the card in English with the spaces replaced by an underscore and the simple quote removed. For example, for the card "Abu Ja'far", you will have the file src/main/resources/tbs/mtg/recycled/Abu_Jafar.xml.
For now, only the game Magic: the Gathering is implemented in Firemox.
A really useful tool has been created in order to increase the XML card creation process. The 'oracle2xml' command allows you to create the whole XML of all cards from a text Oracle file. You can get it from the regularly updated site here or from a ready to use file there and place it in the directory to create etc in the root directory of MP. Then, you can launch the 'oracle2xml' command from the root directory of MP; then, have a look in the etc/xml to see the generated XML files. They can be edited and moved in the tbs/mtg/recycled directory when you think they are well formed and suit to the rules to have MP considering them.
It's advised to build all new cards from this tool since it will save you a lot of time and assure that you are creating cards the right way.
PS: since the Oracle file may have a different name on the the day we created this document, you might have to edit the 'oracle2xml' or 'oracle2xml.bat' command an update the Oracle file name.