The battle system has some randomness to it, but the speed of your digimon is the value that influences who will attack. I have plans to rework from scratch the battle system, but that would be in the future
Viewing post in Digital Partner Digimon comments
The game is good and I appreciate that you made it. Even though I wasted a lot of time trying to get to the end of the second adventure, I kept playing it. I don't know what the original Digimon battle system was, but I think it just needs to be changed or explained how the moves and attack order work. And one more little tip, it would be good if there was a hint in which adventures which characters you can meet. Thanks for the good work.