Nice summary... It occurs to me that Kaiba HAS to have an opponent; if he doesn't, then he not only becomes bored, but he doesn't have a 'yardstick' to measure himself against. It's the old 'treasured rival' thing; you can't play without someone to play against, and his entire existance is based on challenge. Good thing he loves his brother, because otherwise you'd have a growing chance of automatic rivalry right there; he already has a basis of 'family = opposition' in his head.