Since their invention about half a century ago, video games have come to play a vital role in modern human civilization. I think this is because we modern humans were never designed to live like we do now--sitting in traffic, working in offices, shopping in stores. We are, by design, hunter-gatherers. Millions of years of evolution have wired our brains with an inherent need to hunt, gather, explore, solve puzzles, form teams, and conquer challenge after challenge in order to survive as we claw our way to the top of the food chain. For most people, day-to-day life no longer requires many of those experiences or challenges, and so those primal, instinctive needs inside us have no natural outlet. To keep our minds and bodies healthy, we have to simulate those old ways in the midst of our modern, technological lives, where everything on the planet has already been hunted and gathered. Thankfully, the technology that created this problem also gave rise to its solution--a way for us modern city dwellers to exorcise our inner evolutionary demons: video games.