Sleepless Knights Puzzle

Solve two difficult puzzles using only knight hops as moves. Challenge 1 uses 16 knights; challenge 2 uses nine knights. Scramble the board, then recreate the original setup by clicking knights that can move into the empty space.
The only moves allowed are knight hops: two steps in one orthogonal direction, then one step at a right angle. The target position must be empty. (In challenge 2 you sometimes also have to click the desired target position if there is more than one.)
Challenge 1 has one empty square in the lower-right corner; challenge 2 has four empty squares.
The "select" buttons let you take back a move, return to the original scrambled board, go forward one move, or jump to the last move recorded.
Click the "reset to start" checkbox to return to the start.


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Challenge 1 was first published by the same author as the main variant of the Zillions game "16Plus".
Challenge 2 was first published by the same author as the main variant of the Zillions game "9Plus".
Enjoy and don't let the puzzles cause you sleepless nights!
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