Agahnim's Tower
From TLoZ: ALTTP Hacking Resources
This is a subpage of Dungeons
Description
The Lightning Lock guards the entrance of Agahnim's Tower, and it can be destroyed by the Master Sword or higher level sword; or bypassed with the Magic Cape. The lighting lock can also be destroyed by the hammer if you possess any sword level other than $01, including $00. The boss of this dungeon is Agahnim, and defeating him advances the game phase (byte $7EF3C5) to $03. The player is also teleported to the Dark World and allowed a limited access of this world, which expands when the Magic Hammer is acquired.