A standard 9x9 sudoku is hidden somewhere in this tournament bracket.
Within the sudoku, digits along green lines must differ from their neighbors by at least 5.
Within the sudoku, digits in cages sum to the "seed" in the top-left corner (if given), or to the seed that advanced from the previous round (e.g. if the cage in r14c4-5 is in the 9x9, its digits must sum to either 5 or 12).
The cages in column eight represent the two finalists, and the cage in row eight represents the tournament champion (i.e. its sum must be equal to the sum of one of the cages in column eight).
Cells outside the 9x9 sudoku do not contain digits, but a seed can advance through the bracket even if it was outside the 9x9 in a previous round (e.g. the cage in r11-12c6 may sum to 5 or 12 even if the cage in r14c4-5 is outside the 9x9). A two-cell cage can be half in and half out of the 9x9 sudoku, but in that case the cell in the 9x9 must contribute the entire cage sum.
If you or someone you know might enjoy a weekly set of puzzles that are pretty approachable by LMD standards (much more so than this one!), check out Artisanal Sudoku
. Primarily killer sudokus, often in combination with other rulesets.