The dots given in the grid are the centers of pointsymmetric 'galaxies' (ie orthogonally connected groups of cells), which function as cages for the killer sudoku. The number above a dot indicates the sum of the digits in such a cage. The digits in a cage may not repeat. Contrary to a classical galaxy puzzle, not every cell in the grid has to be part of a galaxy.
The shaded areas contain the same digits in the corresponding cells. For example r2c3=r9c8 and r3c6 = r8c5.
The puzzle is also available on Penpa in two versions: as seen above or more space for numbers and shading
Inspired by Galaxy Killer Sudoku by Phistomefel and Sandwich Key-Clone Sudoku by Marijntv Thanks for the ideas! (and the rules, some of which I have brazenly copied :) )
Have fun!
Hints for the beginning:
Solution code: 1st row, then 1st column
on 4. July 2020, 20:55 by Xavien
That was really beautiful, I struggled through most of this puzzle, but when I finally caught on, I was really impressed.
on 28. June 2020, 14:33 by Madmahogany
This was a very nice construction!