Fill in the grids so that every row, every column, and every 2x2 box contains the digits 1 through 4. On the same place in the grids (i.e. in cells with the same color) also the digits must be 1 through 4.

This is a three-dimensional sudoku. Fill in the grid so that every row, every column, and shaft contains the digits 1 through 4.

Fill in the grid so that every ring, marked quarter and cells of the same color contains the digits 1 through 8.

Fill in the grid so that every ring and every green segment with its both yellow neighbors contains the digits 0 through 9 and the letters A and B. There is only one solution. You can find it by logic.

Fill in the grid so that every ring and every green segment with its both yellow neighbors contains the digits 0 through 9 and the letters A and B. There is only one solution. You can find it by logic.

Fill in the grid so that every ring, spoke, 3x3 box and every colored spiral contains the digits 1 through 9.

Put the numbers 1 through 7 into the hexagonal cells so that every line (of any length) and every zone of 7 cells marked by the rings contains every digit not more than once.

Example:

Puzzle:

Put the numbers 1 through 7 into the hexagonal cells so that every line (of any length) and every zone of 7 cells marked by the rings contains every digit not more than once.

Example:

Puzzle:

Put the numbers 1 through 7 into the hexagonal cells so that every line (of any length) and every zone of 7 cells marked by the rings contains every digit not more than once.

Example:

Puzzle: