I got this move that I am not sure works or not.
I got a samurai puzzle, the middle 9x9, the upper left house shares the house with the another 9x9 sudoku, which is the upper left 9x9 Sudoku that shares its bottom right house with the middle 9x9 Sudoku's upper left.
In this house, I got a box with 7 and 9. Well in the same 9x9 Sudoku, to the right in another house but same row, is a 3 and 7. From the 7 and 9 box, if you go left into the other 9x9 Sudoku, but still in the same row, I got another 3 and 7.
So I got a 79, with a 37 on each side in same row. Normally if 1 normal Sudoku, that would allow me to erase the 7, and make it a 9. However, I don't know if that rule still applies when doing Samurai, using pencil marks from two houses in different 9x9 Sudokus. I checked my solution sheet, and it does show that the 9 is the correct answer but I need to make sure it is a legit move.