Betray the kingdom ("Dragon Warrior 1"")
"Rescue the Princess before you fight the Dracolord. Take her with you to the final battle and the Dracolord will ask for her. You have now have the choice of answering "Yes" or "No" to his request.
Easy money ("Dragon Warrior 1"")
"Find a place that sell repellent for 12 gold. They will pay you19 gold if you sell it to them, or anyone else that buys items from you. Buy as many repellents as you can, then sell them to someone. Buy, then sell, and repeat.
Go to the place that sells keys for 16 gold, then exit and re-enter. Sell them at a weapons shop for 26 gold, which is a larger profit than the repellent trick.
In the NES version, if you choose to join Dragonlord you are put to sleep and you get a game over. In the Game Boy Color version, you awaken at Rimuldar. Also in the Game Boy Color version, he offers you half the world; in the original, he merely asks you to join him.
Renaming The Prince of Cannock and the Princess of Moonbrooke ("Dragon Warrior 2"")
"To rename these two party members to a name of your choosing, within 4 character limits, save your game and choose to rest. Resume the Dragon Warrior II game, and enter the "Continue/New Game/Option" menu. Choose "Continue" to where it shows your log files. Place the arrow next to the log file where you would like to change the names, and enter one of the following codes.
Prince of Cannock
Hold [Left] + [Select] + [Start] and press
[A]. The rename prompt should appear for him.
Princess of Moonbrooke
Hold [Right] + [Select] + [Start] and press
Defeating Metaly: ("Dragon Warrior 1 and 2"")
"Go to a store and buy three torches. When you encounter a Metaly, throw the three torches at it (if it does not run away before you throw them).