Sometime possibly before the events of the How to Train Your Dragon Movie, Bob became a "sled" for Astrid and Hiccup to ride in a winter competition called "Bobsledding". The two kids rode on his back as he careened down a snowy mountain, steered by his helmet. At one point, they ran into his Wife's laundry. Bob won the gold metal for the event.
Bob is a typical adult Viking with a full dark brown beard and grey eyes. He has a brown short-sleeved shirt with simple metal pauldrons.
Bob only appears in this DreamWorks Winter Olympic Tribute video.