And @Jzyehoshua again, if you hadn't realized, the game does not host any server-side saves. The maker of this game runs a truely free game setup, so that means he cannot afford to run a large server with all your game info on it. So if you are switching between computers or devices, and thinking to play the same game on each, you are out of luck. Each device will have a separate and distinct save.
@tanstaafl28 search your file system for "#nulllgames\saves", then, to start an alternate save before you begin the campaign, make a new folder and copy the "HDX00.sol" file to this new folder. It will sit there safely for you to use later to rewrite the ongoing save. Or, to wipe your record clean, and start fresh with the base cards again, simply move (don't copy) the file to this new folder. Or, you could delete it completely if you're ballsy and never want to go back to what you had.
@JZyehoshua The reason there is no "save" option for you to hit is that everything is automatically saved to your computer after you win/loose a match or get/upgrade/trade a card. If you want to mess with making "save points" follow my suggestions to tanstaafl28.
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