cover-Xtreme

Size:

21x21.

Elements:

1, 2, 3, 4, 5, 6, 7, 8, and 9.

Groups: One hundred forty-three total.

The 36 rows in the upper left, upper right, lower left, and lower right puzzles.

The 36 columns in the upper left, upper right, lower left, and lower right puzzles.

The 36 3x3 squares in the upper left, upper right, lower left, and lower right puzzles.

The 8 diagonals in the upper left, upper right, lower left, and lower right puzzles.

The 9 rows in the center puzzle.

The 9 columns in the center puzzle.

The 9 3x3 squares in the center puzzle.

Instructions:

Precise details on group numbering.

Answer grids:

Puzzle Difficulty levels and Examples

Difficulty Level	Low	High	Example
Easiest	2	2	Puzzle   ·   3-steps   ·   All-steps   ·   Solution grid
Easy	3	4	Puzzle   ·   3-steps   ·   All-steps   ·   Solution grid
Medium	5	8	Puzzle   ·   3-steps   ·   All-steps   ·   Solution grid
Difficult	9	14	Puzzle   ·   3-steps   ·   All-steps   ·   Solution grid
Challenging	15	20
Tournament	21	29
TournamentPlus	30	45
Perplexing	46	60