There's bug...
Play Diff: Expert
Used Mod: God + Perfect modifier (IDK another modifier, but non-God still same)
Detail:
The Beatmap doubled, there's other beatmap loaded, I think it's from another difficulty (since it's have the same timing with the song)... At the end, only 1 will displayed (but you can tap at notes that already gone). Both can activated, once one used, another will gone, but the rest beatmap still doubled.
(Like, say 1 song have A-B-C group of beatmap/notes, group A appear then you tap on Expert notes, Hard notes will gone, then when group B appear, it's doubled again)
something like that, can't make sure about more detail (I already stop playing the game)