IM Vishal Sareen believes that good chess material is easily available as on today because of authors like Jacob Aagaard. Vishal has used positions of Aagaard for his numerous trainings and has a huge database of some amazing exercises. In this article he shares four brain crushing problems from Jacob's books. It's a two hour test. Have a crack at it, and when you are done, you might want to think about a coffee with Yakub! :)