I have a hard one today:
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If you can solve it all without moving the pieces, you are probably 2600+ strength.
If you can solve it with moving the pieces in a reasonably short amount of time, you are probably 2400+ strength.
Myself and five more people, all rated above 2000, tried to solve this with moving the pieces, for about 20 minutes, and we failed. We got really, really close, but could not piece it all together. It really shows how deep is the game of chess
Give it a try!