The “Inside Sin” location is a dungeon-like area that makes up the final locations of the main story of the game. You can go “inside Sin” after you defeat it and it falls down to Spira.
Inside Sin is full of fiends that you will have to battle as you travel your way through the area. The area itself is made up of a number of subsections including the Sea of Sorrow, the Garden of Pain, the City of Dying Dreams. There are also a few final areas the make up the final battle zones where your team will confront the final boss. These include the Tower of the Dead, The Nucleus and Dream’s End.
You can leave this area and return later on if you wish to complete any of the end game side quests that are available. Once you enter the Tower of the Dead, however, there is no turning back. Refer to the walkthrough and strategy guide section for help defeating the Final Fantasy X final boss:
