What level Sudoku is hardest?

What level Sudoku is hardest?
Techniques and Costs

Level
Lowest Difficulty Score
Highest Difficulty Score

Medium
5300
6900

Tricky
6500
9300

Fiendish
8300
14000

Diabolical
11000
25000

Techniques and Costs
Level Lowest Difficulty Score Highest Difficulty Score
Medium 5300 6900
Tricky 6500 9300
Fiendish 8300 14000
Diabolical 11000 25000
See also  How a Canon Avatar Game Was Created