Odyssey 500
With the same trio of games as the Odyssey 400 - Tennis, Hockey/Soccer and Smash - the Odyssey 500, released in 1976 by Magnavox, would appear to not be much of an upgrade, but in fact, it’s an absolutely critical turning point for home video games: the Odyssey 500 did away with squares and rectangles to represent the player, and introduced character sprites - hardware-generated characters that roughly mimicked the shape of a human being.
Well, very roughly.
It’s easy to understate this development, but it’s just as easy to overstate it too. The stick-figure characters weren’t specific to each game, but selectable: players could choose to play Smash with the sprites from Hockey, for example, and any portion of the character could collide with the ball and be legal for game play purposes - conceivably, bouncing the ball off of the characters’ hands in Soccer was fair game. But given that collision detection programming was now required for a more difficult-to-define screen character than a 
simple rectangle, the Odyssey 500 was still quite a feat. The mix-and-match nature of the character sprites also had its own novelty value: try playing “Battle Tennis” sometime by playing Hockey/Soccer with the Tennis character set.
Again, Magnavox provided an AC adapter with the unit, and was still apologizing for the 1972 marketing debacle by assuring that Odyssey 500 worked on “any brand…any size TV…color or black & white.” Though ironically, it would be a while before one of the Magnavox Odyssey consoles featured color graphics again. For all of its technical innovations, the Odyssey 500 is a high water mark of the early Odyssey games.
