Ideally you'd want someone who has followed Leverkusen a little closer this season to answer that question

but i'll try.
From what i've seen they do want to control the ball, but can play on the counter as well. Press yes, but not a vintage Dortmund counterattacking team.
Bailey is a huge loss. He'd have given Danilo nightmares most likely. Havertz, Amiri and Volland the ones to watch out.
They have some quality players, but if we show up and take them seriously we (have to) pick up the three points.
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Also what Badass said.