714144ed_Lost_Isle___Zelda_Dungeon_Wiki__Description
[Item/ Destination] Boss Key [Description] 
From the beginning; head down, left, down, right, down, left, shoot the mirror there with the Power Rod to reflect the magic into the switch. Head up, and hit the switch to lower the blue blocks. Head down a screen, right two screens, and jump into the southern hole to go to the Dark Side. From there; head right, up, right twice, left, up (through hidden path below the bridge), and jump into the northern hole to return to the Light Side. Head down, left, and shoot the mirror there with the Power Rod to reflect the magic into the switch. Head up two screens, kill all Stalfos here, and continue walk up a screen through hidden path below the bridge. In the next screen; shoot the mirror there with the Power Rod to reflect the magic into the Stalfos there. After they all die; head right, and step on the blue switch there to create a shortcut. Head left, up, right, and hit the switch there to lower the red blocks. Head left, up, right, up, and kill all enemies here. Slash the lone bush in the north-west to uncover the switch. Step on it, then head right, and shoot the mirror there with the Power Rod to reflect the magic into the switch. Jump into northern hole to go to the Dark Side. From here; Head right, and push the stone block into the eastern hole. Head right, down, and then up through right most path. Here; you must hit and shoot the crystal there in the right order. When you're done; shoot the mirror there with the Power Rod to reflect the magic into the Stalfos there. Push the blocks there, and jump into northern hole to go to Light Side. Head down a screen, and slash the bushes there to uncover the green portal. You can step on that portal to fight some Zols that will always drop magic decanter. When you're done; head up, right two screens, down a screen, left a screen, and jump into southern hole to go to Dark Side. Shoot the small hole in the north-eastern wall with arrow to open the door. Head up, shoot the mirror there with the Power Rod to reflect the magic into the switch, and open the chest for the Boss Key.
Lost Isle - Zelda Dungeon Wiki
Description