Pokemon: The Origin

If you like stories that don't feature Ash and want stories featuring the side characters, Pokemon Housoukyoku / Pokemon Chronicles is a great anime that features episodes with Pokemon side characters. Its also got more comedic moments then Origins does. 

In both anime, there is a young protagonist who sets up to become the best at his field: Yugi tries to become the best duelist, while Red tries to become the best Pokemon trainer. Also, in both anime, the main character engages in duels with other characters using their monsters: in Yu-Gi-Oh!, the monsters are summoned through cards, while in Pokemon, the monsters are summoned through Poke Balls. Both anime show the adventures of these characters as they make new friends, but also new rivals. 

Both originated from old games and give guide lines on how to beat them. They also have their on spin-off of the game. While Druaga only contains one scene where the characters actually play the game, Pokemon follows the game up till the battle with Mewtwo.