Lockout Lines can be counter-intuitive, to a point. Instead of the digits between two numbers, you want the digits not between two numbers. Normally you can work out “these are high, so those are low,” but with lockout lines, you could end up with both high and low digits together.

Rules:
Normal Sudoku rules apply.
Digits within cages sum to the total in the top left corner of the cage.
All lines are lockout lines. Digits along a blue lockout line are NOT between nor equal to the digits in the diamond ends of the line segment, and may repeat if allowed by other rules. Digits in diamonds for a given line segment have a difference of at least 4.

Estimated difficulty: 1.5 out of 5

Solve on SudokuPad