Though the difficulty rating is surely wrong - this is one of the tricks you learn on the way to juggling 5 balls and by the time you've got to 552 you are almost there.
I used to practice this pattern obsessively - the 3 different heights of throws are hard to get right but when you do the pattern clicks in and it feels great!
Mill's Mess. Once you've mastered this, you've mastered 3 balls!
https://libraryofjuggling.com/Tricks/3balltricks/MillsMess.h...
This 5 ball multiplex is a fun one to learn - look like you are juggling 5 balls but you are only really juggling 3.
https://libraryofjuggling.com/Tricks/5balltricks/FiveBallSpl...
Here is my favourite 4 ball pattern
https://libraryofjuggling.com/Tricks/4balltricks/552.html
Though the difficulty rating is surely wrong - this is one of the tricks you learn on the way to juggling 5 balls and by the time you've got to 552 you are almost there.
I used to practice this pattern obsessively - the 3 different heights of throws are hard to get right but when you do the pattern clicks in and it feels great!
https://libraryofjuggling.com/Tricks/4balltricks/534.html