It's been reported that Minimax has one of the most devastating critical hits in this game. Shindo has to be present at Max with Nobunaga in order to hold and fire the minimax. After you've read the instructions for the level, all you need to do is keep holding down the D-pad for a while. After reaching full charge, you would trigger the yellow maximum. If you simultaneously pressed the button in a rapid manner, you would achieve the minimax effect.