The Legend of Zelda

The Legend of Zelda
Developer: Nintendo Publisher: Nintendo Platform: NES Released in JP: February 21, 1986 Released in US: August 22, 1987 Released in EU: November 15, 1987 This game has a notes page This game has a prototype article This game has a prerelease article

The Legend of Zelda features Link on a quest to save Zelda from the evil Gannon (sic!). On his way, he gets no help at all except for the Old Man who gives him a random stick he picked up somewhere (plus some vague hints), and is on his own in the vast land of Hyrule.

Unused Enemy Values

0350 - Monster Modifier
 18 - Strong enemy that resembles Digdogger, only completely graphically corrupted
 25 - Strange non-killable object that flies in a circle
 26 - Nothing? (Puff of smoke) (may be replacement data for cleared-out rooms)
 29 - Nothing? (Puff of smoke) (may be replacement data for cleared-out rooms)
 53 - "meteor shower" effect
 54 - "meteor shower" effect
 5A - "meteor shower" with Blue Lynel sprites

Hearts on Menu

0650, 0651, 0652, 
0653, 0654, 0655 - Heart total and damage on loading screen
Damage taken by the player is never saved into RAM in the final game

Unused Spawn Type

Via the use of world scrambler codes, you can force enemies to spawn from an unused configuration; all the enemies will rush out from a single cloud of smoke.