Recreate the original setup using only knight hops.
To start, click the "scramble" checkbox. Then click one of the tokens.
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.
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.