one difference that i noticed from guitar gameplay is that for multiple drums hit at the same time, they count separately towards your multiplier. So if you are hitting RY-RY-RY-RY-RY, after five such hits that will get you to 2x, which is different from how it works for guitar. In terms of numbers this means the penalty for dropping a note from a 4x streak is fixed at the lowest value rather than variable like for guitar (where if you drop in the middle of a section with a lot of chords or sustains the effective penalty is higher compared to if its all single notes)
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Watching her, these things she said / "Time," she cried "failed to wait, this time"
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Hush now / Let it go now / I know it's time to go / Time to let this fall / From my hands