Difficulty score 20. No green.

Done

Restart

don

Done

ng/ng

done

Looked to be an interesting and challenging pattern at the start, but as a puzzle it was disappointing. There should be a name for such puzzles. Chach-Key Sudoku?

ngng

start

ding

... or maybe a Bling Board?

go

done, ng

to

er, go even

done

Easy enough. But it had a pretty nice pair, difficult to spot because the two exclusions were not in parallel. 18.

done

Done

go

done