Zelda II: The Adventure of Link/WMG

Link is drawing power from the Triforce of Power.

 * Think about it. We never find out what happened to the triforces between the first game and this one. Last we saw, Ganon's triforce was in Link's hands. This would explain why Link can level up (which doesn't appear in any other Zelda game) and use magic (which usually requires at least some sort of tool or fairy power). It also explains why killing Link might be able to bring back Ganon, and why the final boss is Dark Link rather than some external evil.
 * Actually, we do know what happened to the Triforces after the first game. In the ending you see Link using all three Triforces to awaken the Sleeping Zelda. This means that Link was carrying the Triforce of Wisdom and the Triforce of Power with him for the entire game.

That's not a mistranslation or an example of Engrish -- his name really is Error.

 * This was confirmed by Nintendo. Error really is supposed to be his name.
 * Stole this one from the Urban Dictionary. Basically, the idea is that Error and Bagu (Bug) are meant as some sort of Theme Naming, perhaps meant as a joke of some sort.

Kasuto is...

 * OoT Link. It's an Embarrassing First Name and prefers Link.

The Map is rotated 180 degrees.

 * The kid in Ruto gets some grief in Duane and BrandO's song about the game, considering west (The direction he tells you Parapa Palace is) takes you off the edge of the game map... or does it? Remember, in the first and third Zelda games, Death Mountain is in the north part of the map. Where is it in this game? The bottom of the map. If it isn't a bad translation, it could be one part Interface Screw, one part Mind Screw that the map in Zelda 2 is actually turned around.
 * The reason Death Mountain is in the south is the whole Zelda 1 map is in the southern corner of the map. The rest of the game just takes place north of Death Mountain.
 * Jossed, the FAKE TOMB Error of Ruto mentioned is actually directly south of the KINGS TOMB. Which means...
 * With the way the dialogue is written, it can be confusing. However, the kid says "GET CANDLE IN PARAPA PALACE. GO WEST." What he means is "Get the candle in Parapa Palace and then head west." Remember, the cave you have to go through using the candle is in a valley west of Parapa Palace. That is what "west" refers to, not Parapa Palace.

The kid in Ruto fails geography forever.
Please explain.