This book comes from puzzle sensei Rich Norris, one of the most prolific authors of the New York Times crosswords in the last 20 years. It includes 300 tricky puzzles. These brown belt clues add wordplay and trivia to the mix, upping the difficulty and increasing the enjoyment. Ready for a real mental workout? With puzzles this advanced, you'll need to stay sharp. These brown belt clues add wordplay and trivia to the mix, upping the difficulty and increasing the enjoyment.