ok, I've heard from other people that remix 8 is one of the hardest ones in the game because of it's speed. Well, here are some tips that may help you beating it:

-at the beginning and the end of the song, the game continuously switches between the ninja dog and the table tennis guys, which will make most people panic, but the trick at these points is to keep the same rhythm, because, even though it switches all the time, both the dog and the table tennis thing have exactly the same rhythm here.

-just after the first part, the drum part will come. at this part there is another little trick. the red drummer will play a simple beat, but right when it switches to you, the red drummer will play one last note. this is made quite unnoticeable so you have to hear carefully.

that's it for the hard parts of the remix. i hope it helps!!!