Dr. Mario

Released by Nintendo in 1990 and developed by Gunpei Yokoi's team, Dr. Mario is a falling-block puzzle game starring Mario as a physician. He drops red, yellow, and blue vitamin capsules into a bottle full of viruses; players rotate and stack the capsules until four of the same color align horizontally or vertically, eliminating the viruses in the chain. Let the bottle fill without clearing them and the game ends. The soundtrack, composed by Koji Kondo, features two enduringly catchy tracks — Fever and Chill. Adjustable difficulty and a lively two-player versus mode made Dr. Mario one of the defining casual puzzle titles of the late NES era.