Let me help you with something that I came across, I know a few people like to play games in their time out and I am no different.
I came across a little helper in the game to those wanting to keep the Combo Bonus going a bit longer.
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And from what I can see is that BP (Batle Points) Are hard to come by.
From what I have worked out, if you battle and don't press next to get to the next screen the countdown does not begin until you have clicked next, very handy. So if you are casually playing you can start a battle, leave the device for 5-10 minutes and then press next and the combo timer starts at 10 minutes, handy while charging up your BP's.
Last night I got my Current Winning Streak up to 21 before I ran out of EP and BP. Better than my usual max of 8.
I have found that walking away for 30 minutes doesn't work, I am not sure of the exact time that you can leave it before the counter is cancelled. If you work it out please comment below.