It is possible to skip most of the Dark Maze you're supposed to go through to access Dark Palace. Using a non-damaging item (The Sand Rod is probably the best choice here, though in the fastest any% route only the Hookshot is available), push the Snapdragon (the one near the first cell) northeast, all the way in the corner made by the tree and the ledge. Stand on the left side of him as he is waking up. As soon as you take damage, run into the corner while you are invincible and use the Tornado Rod. When Link lands, he will be facing the north-east direction. Tap the control stick to the right so he faces directly east and dash using the Pegasus Boots. He will bump into the tree and fall on the ledge. From there, walk along the ledge to get past that one guard. Be careful not to get caught by another guard after the skip, because you will be thrown into the second prison, which is about halfway into the maze, making it necessary for you to actually complete the thing.
Be EXTREMELY careful when orienting Link before dashing. If you don't do it properly and dash in the north-east direction by accident, he will fall into the water. If this happens, it is still possible to save yourself to try the skip again.
Normally, you would have to reset or void out until you die, but it is possible to fly out of the water using the Tornado Rod. Below the bridge is a spot you can swim into and void out. If Link dives into the line where water turns into void, he floats out of the water and for a few frames can use the Tornado Rod before voiding out. Doing so means you can Tornado Rod up through the bridge. You'll be caught by the Lorule Soldier but will be able to try the skip again.
The black box is the spot where water transitions into void.
Using a precise dash slide, it is possible to get on the green wall area right outside Dark Palace. This is useful in 100% for getting the heart piece and maiamai in the maze, though it only saves a little bit of time.