To make it short Gannondorf made the Sand Realm really big to bring the Gerudos back, and he created a new floor on the Tower of Spirits and that floor is supposed to shackle the bigger Sand Realm to Hyrule, but there are no shackles/tracks on the bigger Sand Realm and the new floor could get torn off, along with the other floors and release something (maybe Malladus) that was shackled under the tower, and I guess tour characters have to shackle it down. I guess they would do tasks for the Gorons and Whittleton Villagers to get metal and wood to get train track materials and create track/shackles. Then, they have to defeat Gannondorf. If the new floor tears off any others, they must shackle that other floor back down by getting that rail map.
I need help thinking of a title.