I know a few of you are in to this kind of thing (mainly you YGO fans) and I cane across this program the other day so I thought I'd share.
It's called
LackeyCCG and it's a program used to organize decks of any card game. It saves the entire series of cards on your computer and allows you to build and save decks. It doesn't, however, have any sort of rule enforcement, so you and your opponents will need to know the rules (and both behave yourselves)
Using it is a little complicated, as it's still somewhat in beta. The game hosting works but it took me a while to figure out how to download plugins (a.k.a. the sets of cards) so I'll give you a little of what I know.
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To get plugins for some games you go to the preferences tab and then plugins, select it from the list above the second small box, and I find the "visit plugin website" button yields best results. If the one you want isn't there, you need to find and download it yourself.
The plugins should come in one folder named after the game so all you do is move it to the Plugins folder in the lackey window. (had enough of the word plugin yet?)
To chose what game you're using, it's at the top of the preferences page under "Plugin Preferences" click browse and chose your game from there. NOW you can build your deck. Really easy, go to the well named "Deck Editor" tab and drag the cards from the list at the bottom on to the top, name it and click save deck. Some plugins have more than just the "Deck" option, say for games that require character cards. You can go play now.
At the game screen you first need to load a deck. Do so by right clicking your avatar at the right and use the load recent deck option. You control actions by right clicking the cards or the blank space around the play field. At the bottom right there are phase buttons for your convenience. Health/score is beside players avatars. Games that use custom play fields can load them into Images>Backgrounds. You can also find an avatar folder there too. If you're having trouble reading a card theres a checkbox at the top right corner below where it displays the last card you hovered your mouse over.
Finally it has a game hosting feature, looks easy enough to use. You might need to turn on PROXY features or something though. Oh, and there is NO computer player option.
Again I know some of you play YGO and there were talks of an SPC card game so this sould be of some use at least.
I'll try to look in to and questions you have.