Yu-Gi-Oh! Duel (iPhone iPod)
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Various General Tips
The majority of your deck should be comprised of 1-4 star monster so you can cause attrition to your opponent while you make way for better monsters.
Trap cards are as sneaky as they come, take notice of what type of cards your opponents tends to be using and deploy the trap card accordingly.
Utilize Card Trader as much as you can as it is greatly organized in this game.
Gems can be earned easily through daily login bonuses, leveling up, and completing missions.