Recapping the last event, Darunia followed the Zelda lookalike's orders, so the group is now going to Lake Hylia in order to find the source of the trouble. However, there is one problem: only Zoras can swim and battling underwater is very unlikely, especially without a supply of blue tunics.
Veterans should recognize not just the three-level Water Temple (redesigned for the purpose of this game in order to follow the vein of the Dynasty/Samurai Warriors series) and the fishing area where you can fish for the largest fish in order to get a prize. For now, Impa, Sheik, and Darunia, leader of the Goron tribe, are aiming to get to Evil Zelda and close the "Gate of Souls." As recommended, go with Sheik.
Saving Princess Ruto[edit]
Since she's the "key" to the Water Temple, you have to protect her from Lizalfos and Poes while taking her to the base in order to drain the water down and gain access to the Water Temple (as opposed to using your hookshot underwater to open the door in Ocarina of Time).
Race around the temple[edit]
Princess Ruto will go to the middle to get the "Lens of Truth." Again, veterans should be familiar with this but for those who aren't, the "Lens of Truth" briefly reveals what's "real" and what's not. It's put to great use at the "Bottom of the Well" and "Shadow Temple" at the Graveyard.
Back to the task at hand, you need to not only drain more water from the bottom corners of the southeast and west, but you must also save Darunia outside the entrance of the Water Temple. This should be easier if you're playing on the 3DS/Switch version, with the ability to change between Sheik, Darunia and Impa.
As soon as you finish draining the water by conquering two key bases on the south end of the map, go to the middle southern area to battle the gatekeeper and unlock the middle area. If Princess Ruto is in danger, you'll see a green circle. Race to the green circle so you can automatically heal the Zora to full strength.
Dodongo and Evil Zelda showdown![edit]
If you think you're nearly finished, think again! Evil Zelda calls Dodongo back! To keep the fight short, follow this pattern: as soon as Dodongo sucks the air in, throw in the bombs and attack its weak point (by the circle) approximately two to three times.
The "Lens of Truth" should open the boss area located at the bottom south, though you'll find the door south from the middle area. You'll have to battle hard since Lizalfos and Poes can be found there as well. Once you finish battling Evil Zelda, the level should come to an end.
The following cutscene reveals that Evil Zelda is actually Wizzrobe, and Sheik is actually Princess Zelda?! They both magically close the portal and that ends the tour of Ocarina of Time. So what happened to Lana and Link while ending this war? You'll have to play four more levels to find out: two in Twilight Princess and two in Skyward Sword.