Yu-Gi-Oh and friends are here for a tournament hosted by Kaiba Corporation. You must obtain 6 locater cards in order to get into the tournament. To obtain these cards, you must battle various people around the city. As you battle the duelists, you have the opportunity to gain new cards (if you win), or lose cards (if you lose). There is also a card shop if you want to buy cards rather than using only what you get from antes.
The battles are played just like the in trading card game. You use your cards' effects and strengths to defeat the other players' cards. By lowering their life points to 0, you will defeat them.
A feature in this game is your duelist level. Cards have certain levels on them. If your duelist level is below that number, you cannot have that card in your deck. This is a new feature not seen in previous games. This feature keeps you from just buying all the best cards at the start and having an easy time for the rest of the game. By winning duels, you will gain in level quickly enough to start using some of the better cards, though it will still take some time to be able to use the best cards.
Can you get into the tournament and win the 3 Egyptian God cards? Yu-Gi-Oh and his friends are also trying to get into the tournament. So you'll have to beat them in the tournament to win everything. The game features over 900 cards and over 100 duelists.