Yu-Gi-Oh! 7 Trials to Glory Hints for Gameboy Advance
If you want to get better cards, I suggest saving your DP. You can get decent DP from the following ways(should always work)
1.Dueling Tea(uses alot of cards that brings her LP up, you get DP also based on amout of LP damage you deal)
2. Spending little to no money from tournament(Weekend tournament = 1000 DP total. Limited Tournament = about 300-700 DP per opponent. K.C Cup= varying depending on round the more into the tournament you get the more money you get each time.)
Ive gotten all 5 exodia pieces 4 times easily, but it does require patience
**SPOILER**
I got the Exodia pieces from the Super Monster Pack(500 DP per pack and 5 cards per pack)
This should really help your game, as well as skills 
Disturbed32595
If you're having trouble beating a certain opponent in a tournament you could just restart your GBA before it saves ur lose.(best time would be when it says "You Lose")
I know its simple right? You should already saved the day of the tournament once you start up your GBA again it should take you right back to your house and it should still say the name of the tournament by the door when you go out.
Hope this helps. It helped me alot 
Disturbed32595
No thumbs
yet
An easier way to get DP is if you keep dueling Tea.
I know it sounds boring but u also get DP dapending on how many Life Points you deplete from your opponent. Tea uses alot of cards that increases her Life Points,(such as Nimble Momangan which when its destroyed and sent to the graveyard she gets 1000 LP plus 1 or 2 more of them to her field which means 2000 more LP when you destroy them.)
Hope this helps.
Disturbed32595
Heres a tip that will help you save your points.Dont waist your points on the Guardian cards(for ex:Guardian Kay'est)Those cards are not in the game.Sorry Guardian card fans.
Affter you unlock the Rare Hunters shrine go there on Thursday and look around for Bakura he will be there and you can duel him when he is wearing the Millenium Ring.
Here are the codes for two very powerful cards.
Black Luster Soldier-Envoy of the Beginning-72989439
Chaos Emperor-Envoy of the End-82301904
Hope you like these cards and the best time to use them are in the Rare Hunters shrine.Also you can only enter the codes in the Rare Hunters shrines card code machine.
Duel everyone inside the card shop on Monday.After you beat them all inside the card shop talk to Grandpa Muto and you can enter a tournament on Tusday hoasted by Grandpa Muto.
If you finish the game then at the title screen use this code press Up,Up,Down,Down,Left,Right,Left,Right,B,A to change the title screen to blue insted of purple.Repeat the code to disable the effect.
Put a Time Wizard in your deck and talk to Joey and he will duel you using Time Wizard.
If you made your own Exodia deck then go to the card shop and talk to Grandpa Moto and you will duel him using an Exodia deck.
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