Optical illusions are incredible brain teasers that put your observation skills to the test and question your pattern recognition skills. In this thrilling teaser, you have a grid full of seemingly identical “968s.” Yet one of them is an odd number that is different from all the rest. Optical illusions are incredible brain teasers that put your observation skills to the test and question your pattern recognition skills. In this thrilling teaser, you have a grid full of seemingly identical “968s.” Yet one of them is an odd number that is different from all the rest. Health and Fitness, Health Tips, Exercises & Workout Tips, Diet & Wellness | Times of India Lifestyle