Normal sudoku rules apply.
Stacked Fortress: A digit placed in a light shaded cell must be strictly greater than digits placed in orthogonal adjacent unshaded cells.
A digit placed in a dark shaded cell (marked with a diamond) must be strictly greater than digits placed in orthogonal adjacent cells, including light shaded cells.
Here is the Penpa+ link: Stacked Fortress
Here is the CTC link: Stacked Fortress
This puzzle was originally made for the "Mystery Board Speed Setting Contest" on the CTC Discord, in which it won first place. The challenge was to make a puzzle starting with this grid within 70 minutes.
Solution code: Column 3, then row 8, no commas/spaces
on 1. August 2022, 20:31 by Onkel_Dagobert
Great puzzle, more like 3/5 for me, esp. in the middle game - after an easy break-in, I didn’t know what to do for quite a while.