1-5-9 O'Clock Rock
- Killer cages
- Kropki dots
- XV and number dots
The brief
Normal Sudoku rules apply.
1-5-9: Each digit in column 1 indexes the 1 in its row (i.e if R3C1=4 then R3C4=1). The same rule applies to column 5 digits indexing 5 in its row, and column 9 digits indexing 9 in its row.
Digits separated by an X sum to 10. Digits separated by a V sum to 5.
Digits separated by a black dot must be in a ratio of 2:1 with on another.
The brief doesn't mention the cages. We read them as standard killer cages (a cage's digits don't repeat and add up to its total), which the setter's solution confirms.