Digi-Battle Game Rules
If you want to actually play the Digi-Battle card game you'll need to know the rules. The rules have already been explained in great detail on a few other sites so I'll simply link you to them here.
I may do my own deep-dive of the rules in future but for now I'll just point you to other people who have.
Very detailed guide on digitalindex.ultimatedigimon.com
Watch a YouTube video overview of the game
I have scanned the game rulebook that came with the starter deck so this can be used as a reference to the rules too: View Card Game Instruction Book
Here's the scanned playmat for one player, to use it you can print out 2 copies of this image and turn them to face each other:
