This one looks simple, but I found it challenging to play it at a steady tempo.
All double-strokes (RRLL), quarter-note equals 100 bpm, play it in this order without stopping:
2 measures of 8th notes
2 measures of 8th note triplets
2 measures of 16th notes
2 measures of 16th note triplets
2 measures of 32nd notes
2 measures of 16th note triplets
2 measures of 16th notes
2 measures of 8th note triplets
2 measures of 8th notes
Good luck!
Here's a video demonstration I made:
If you guys have any warm-up challenges, feel free to post them...