Rules: standard Sudoku rules apply, plus each cell can't have the same value as its knight jump neighbor.
Click in the numbers bar to eliminate by hand. Red numbers means only 2 left in a certain group.
Tip: look for double pairs; you can eliminate their numbers from the other cells. Same for groups of 3 per group: eg 123 123 123 or 12 23 13 or 78 89 789 or 789 89 789
Also look for numbers that are remaining in the overlap of 2 groups, eg 3x3 and horizontal, then for the other cells in the other group the number can be eliminated.
Tip: highlight a number by find function ctrl+f