Backslash L(2,3) D(22,8,8,1,1,0)
Difficult
Must have unique characters in each row and column but the 3 by 3 boxes are replaced by backslashes. These wrap left to right and top to bottom so the overall geometry is a doughnut (torus)

Diamond L(2,1) D(25,5,5,0,0,0)
Moderate
Here the shapes are pushed over to become diamonds. This wraps side to side but not top to bottom.

Jigsaw L(2,1) D(23,5,5,0,0,0)
Moderate
As regular 9 by 9 but the normal 3X3 boxes are irregular shapes

Samurai L(2,3) D(114,14,13,1,1,0)
Difficult
Effectively 5 intersecting 9 by 9 Sudoku problems.

Toroid H L(2,3) D(19,13,12,1,1,0)
Difficult
The normal 3X3 boxes are replaced by horizontal stripes (helices) which wrap around the problem. These stripes join the left side to the right side and the top to the bottom so that the overall geometry is a doughnut (torus).

Backslash L(2,3) D(21,14,13,2,1,0)
Difficult
Must have unique characters in each row and column but the 3 by 3 boxes are replaced by backslashes. These wrap left to right and top to bottom so the overall geometry is a doughnut (torus)

Diamond L(2,3) D(24,11,10,1,1,0)
Difficult
Here the shapes are pushed over to become diamonds. This wraps side to side but not top to bottom.

Jigsaw L(2,1) D(26,5,4,0,0,0)
Moderate
As regular 9 by 9 but the normal 3X3 boxes are irregular shapes

Sudoku 9X9X L(1,1) D(24,4,4,0,0,0)
Easy
As regular 9 by 9 but must also have unique characters in each diagonal, highlighted.

Toroid V L(2,3) D(20,19,19,3,2,0)
Difficult
The normal 3X3 boxes are replaced by vertical stripes (helices) which wrap around the problem. These stripes join the left side to the right side and the top to the bottom so that the overall geometry is a doughnut (torus).

Diamond L(2,1) D(22,9,8,0,0,0)
Easy to Moderate
Here the shapes are pushed over to become diamonds. This wraps side to side but not top to bottom.

Film L(2,1) D(25,9,8,0,0,0)
Moderate
Similar to the regular 9 by 9 Sudoku but the squares have lumps in the top and bottom. The problem wraps top to bottom but not side to side so the overall geometry is a cylinder.

People L(2,3) D(19,9,9,1,1,0)
Difficult
The shapes have “lumps” on each side to become quite irregular. They look to me like little people. This problem wraps top to bottom and side to side so the overall geometry is like a doughnut (torus).

Sudoku 9X9X L(1,1) D(22,5,4,0,0,0)
Easy
As regular 9 by 9 but must also have unique characters in each diagonal, highlighted.

Toroid H L(2,3) D(21,11,11,1,1,0)
Difficult
The normal 3X3 boxes are replaced by horizontal stripes (helices) which wrap around the problem. These stripes join the left side to the right side and the top to the bottom so that the overall geometry is a doughnut (torus).

Backslash L(2,1) D(22,7,6,0,0,0)
Moderate
Must have unique characters in each row and column but the 3 by 3 boxes are replaced by backslashes. These wrap left to right and top to bottom so the overall geometry is a doughnut (torus)

Diamond L(2,1) D(28,5,4,0,0,0)
Moderate
Here the shapes are pushed over to become diamonds. This wraps side to side but not top to bottom.

Film L(2,1) D(27,7,6,0,0,0)
Moderate
Similar to the regular 9 by 9 Sudoku but the squares have lumps in the top and bottom. The problem wraps top to bottom but not side to side so the overall geometry is a cylinder.

Samurai L(2,1) D(117,5,4,0,0,0)
Relatively easy but a large problem
Effectively 5 intersecting 9 by 9 Sudoku problems.

Toroid V L(2,3) D(21,9,8,1,1,0)