Having acquired the Titan’s Mitts from the Desert Palace dungeon, the big rocks across Hyrule and Lorule will no longer obstruct you. In particular, there’s one big rock we should focus our attention on first. To begin with, warp to the Sanctuary in Hyrule and go inside the building. At the very end, where Link first encountered Yuga, there is a doorway to Lorule; merge into the wall and go through it. Emerge in Lorule and you’ll be in a dark room. Light the nearby torch block with the Lamp or Fire Rod to get an amusing reaction. Anyway, head all the way down and through the door.
Outside, turn left and lift up the big rock to uncover Maimai #69 . Then proceed right to the next screen. Here, just ahead is Maimai #70 glued to the wall; as usual emerge behind the Maimai to force it off. Next, climb up the stairs to the right and bomb the crack to reveal a doorway to Hyrule. Merge into the wall and go through the doorway. Back in Hyrule, go into the cave immediately to the right to claim a Piece of Heart . Return outside and merge into the wall left of the doorway and walk left to force Maimai #36 off the wall.
Make your way back to the Sanctuary and return to Lorule through the doorway. Proceed to the point before you travelled to Hyrule and continue right. At the end, you’ll be blocked by a fence and a big rock. Cut down the bushes and the skulls and make your way below the big rock, where there’s a weather vane.
From here; head right to the next screen. In the next screen, go down. Here, dash into the nearby rock to dislodge Maimai #70 . Next, head down, minding the shield Moblins–hookshot or burn their shields–and open the chest containing 100 rupees .
Return to the weather vane, a few screens earlier. Go up to the big rock and give it a good pull with the Titan’s Mitts to reveal a secret staircase going down. Downstairs, it’s dark, so flash out the Lamp. Open the chest ahead and up the stairs to earn yourself… 1 rupee!? Continue up and as you touch the water, turn left and smash the skulls to reveal a hidden floor switch–step on it to open the door leading up. Through the door and, by now, you should realise exactly where you are–in the same secret way from the very beginning of the game!
Like in the very beginning, head all the way left. This time, the monsters are slightly tougher and there aren’t any torch blocks to light up, but you should be a tougher Link too. Halfway across the room, open the chest to earn yourself a slightly better, but still measly 5 rupees. At the end, go up the stairs ahead and turn right to get on top of the wire mesh path.
Carefully follow the path right, avoiding all the crazy Chasupas and you’ll come across a chest container an okay 20 rupees. From here, merge into the wall on the right and walk right to collect a Small Key .
Now make you way back left, to where the locked door is; open the door and go through. The next room will lock and you’ll be ambushed by three Eyegores; slay them to unlock the doors. Then head through the door leading up. You will be right before the final door, with two pull switches to choose from. Last time it was the switch in the top-left corner that worked, but not in Lorule; pull the switch in the top-right corner to unlock the door.
Through the door and upstairs, you’ll be in Lorule’s Sanctuary again. Head down and merge onto the wall to the right, then walk right to reach the chest containing a Master Ore . To leave, just drop off to the left.
Assuming you’ve followed the dungeon order in this guide, you will now have two Master Ores–enough to upgrade the Master Sword. When you’re ready, return to Hyrule and visit the Blacksmith’s to get the Master Sword Level 2 ; with this crimson edge, you do extra damage to monsters!