The menu and in-game interfaces are pretty easy to understand. When compared to past games, this is a good thing, but there are still a few problems. The option of importing cards from the card game into the video game has been removed. Depending on your point of view, this can be either a good thing or a bad thing. While it does help to balance the game from keeping people from importing stacks of power cards for their initial deck, it also makes finding certain cards a crapshoot. Granted, this gives you more reason to continue playing the game, the tournament structure can get a little boring after a while. Plus, the chances of actually getting just the right card are slim. The initial deck you start with does contain one of the rare 'power' cards (like a Dark Magician or Blue-Eyes White Dragon), so you can count on at least getting one of those.
While the deck creation menu looking cleaner, it still wasn't the easiest to use. Players are allowed to own up to three decks, which helps keep games fresh since you can change your deck style. An added benefit of allowing three decks is that up to three players could share the same cartridge.
Creating decks is not very easy. Sorting cards, as well as copying cards to other decks and purging decks, is handled via a menu, while the shoulder buttons allow you to place or remove cards from the deck. The issue is that you are never told that the shoulder buttons do anything. Sure this is every bit my fault as it is the designers since I tore into the game without looking at the rulebook, but can you blame me? When you consider that most of the audience for this game knows all the ins-and-outs of Yu-Gi-Oh! already, how many do you think will really give second glance to the rulebook? The system is manageable once you figure out this simple mechanic, but an on screen indicator would have helped.
Fans who were disappointed with the previous two Yu-Gi-Oh! games are sure to enjoy Yu-Gi-Oh!: World Championship Tournament 2004. The return of familiar mechanics with the added attributes of varying play and deck styles does not completely make up for the lack of story, but it helps. While I, as well as many other players, would still love to see the presentation of Sacred Cards mixed with the duel mechanics of the Tournament games, we will just have to take what we can get for now.