Eight Queens Fill

An 8 Queens puzzle that starts with some queens already on the board. Place the rest so that no two queens attack each other. HOW TO PLAY - Tap an empty square to place a queen. Tap it again to remove it - Queens that attack each other vertically, horizontally, or diagonally light up in red - The queens placed at the start can't be moved - Clear the puzzle when all 8 queens are placed with no attacks FEATURES - 4 difficulty levels: Easy, Normal, Hard, and Demon (fewer starting queens means a harder puzzle) - Hints when you're stuck, plus a warning when no solution remains - Clear counts, best times, and clear streaks are saved on your device - No account needed - Free, with no ads and no in-app purchases ABOUT THE GAME Based on the AtCoder competitive programming problem ARC001 C (8 Queens), reworked into a puzzle anyone can play without any background knowledge.