I think this is the hardest Dragon Warrior I've played so far. The levelling up is stiff and your rewards for those levels are slim. Certainly the later NES ones, Dragon Warrior III and Dragon Warrior IV, are much more playable and reasonable with experience points. Even the Metal Babbles in Dragon Warrior II yield little EXP! DWII is pretty weak in the story part but that's to be expected. 

The Prince of Midenhall unites with the Prince of Cannock and the Princess of Moonbrooke. Acquiring the three happens within the first few hours of the game, with the Princess of Moonbrooke being last to join (she was turned into a dog!). 

The Midenhall Prince is a tank that does nothing but attack. Fortunately he is the one who can make the last battles easy. The other two can both heal and use attack magic, although the Prince of Cannock is probably more of a healer / defensive type as opposed to the Princess's generally offensive based spells.

They're saving the world from Hargon and Malroth. In this game you even get to go through Tantegel and Charlock's Castle from Dragon Warrior I. Expect to put in lots of levelling up and go through some insanely long caves but it doesn't hurt to play a difficult RPG once in a while.

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