Sudoku 129 Better

Standard Sudoku puzzles are graded by difficulty based on the techniques required to solve them. Easy puzzles require "Hidden Singles." Medium puzzles require "Naked Pairs" and "Locked Candidates." Hard puzzles require "X-Wings" and "Skyscrapers."

: A popular YouTube resource for deep-diving into complex logic like X-Wings, Skyscrapers, and Chains. sudoku 129 better