Getting to Deku Village (Story Mode)
If the player starts a new file in Story Mode with Symphony of the Mask installed, it is possible to visit the Future World without going through Hyrule Castle. In the Lost Woods' Cadence cave, the player can dig through the back wall to find a Time Portal to the Future World. Entering it will take the player to Skull Kid's house. The player can then explore all of the Future World as Skull Kid, Link, Zelda, Yves, or Cadence. Unless the player has collected the Bongos and the Synth and completed Hyrule Castle, the Lost Woods portal is the only way to travel between Hyrule and Future World.
The Lost Woods portal will only appear on files created since installing Symphony of the Mask. To find out if the file supports travelling to the Future World overworld, check how many instrument slots there are on the save file or inventory. If only four appear, the file does not support the Symphony of the Mask Future World. Files that contain the Lost Woods portal should also have an additional permanent item row (center pane on the inventory screen) and permanent equipment row (bottom pane), and Bottles are stacked in the menu.