Sudoku x 4

The goal of the game (aka Sudoku or Number Place) is to fill in the empty cells, using the numerals 1 through 9, placing one number in each cell so that each column, row, and 3x3 region contain the numbers 1-9 exactly once. Sharpen a pencil, print this page, and get started.

Game:  

6 8           9 1
4 9     1       5
    1   6   2    
      1   2      
  1 6       7 8  
      9   6      
    3   4   9    
1       2     3 4
8 4           7 2
Difficulty: star (score: 89)
Skill Level:

Game:  

8   2 4   9 6    
          3 9    
5         6   4 2
6           5 2 4
                 
1 2 7           6
3 7   6         9
    5 3          
    4 5   8 1   3
Difficulty: starstarhalf star (score: 225)

Game:  

  4         2    
3     4         5
    1   5 8   6  
1         3   9 7
    9 2   7      
4         9   3 2
    4   1 5   2  
2     3         4
  5         1    
Difficulty: starstar (score: 157)

Game:  

  7       2   8  
    1 9 3        
    2       3    
7         9 6   5
  2   3 6 4   7  
6   3 5         2
    5       2    
        2 3 8    
  6   8       9  
Difficulty: starstar (score: 134)
starstarstarstarstarstarstarstarstarstarstarstarstarstarstar
EasyMediumHardVery HardDiabolical