Online:The Fallen City of Shada

Quick Walkthrough
# Enter Shada's Tear.
# Talk to Sali'ma.
# Cleanse the city and crypt wings.
# Defeat Shada.
# Talk to Sali'ma.
 

Detailed Walkthrough
Enter Shada's Tear, either by ladder or by jumping down into the water. Continue about halfway into the first room to talk to Sali'ma, who is looking at the green-tinted water.
:;I've heard that the water's cursed.
:"You heard right. The first researchers to drink the water said it tasted like nothing they ever drank. Made them feel strong, alive. And then they started changing. They attacked us, like we were intruders and they were defending the city."
:;Do you know what caused the curse?
:''"Well, that's where things get truly strange. Seems that this place was built by the Nedes—the ancient people who settled Craglorn before the Yokudans. We don't know a lot about the Nedes, but it seems like these particular ones worshipped Nereids."''
:;You think the Nereids are behind the curse.

He replies that nereids are known for controlling people's minds, and the researchers became thralls of Shada, a nereid. The path to the main chamber is currently blocked by the cursed water. The water flows into the central pool from two wings. If you follow the water, Sali'ma suspects you will find the source of the corruption. Since the main chamber is unreachable, you'll have to cleanse the wings before you can access it. He guesses that Shada, the leader of the nereids, lies within.
The City and the Crypt
The two wings are called the city and the crypt. Both need to be cleansed. Head south down the stairs past Sali'ma, being careful not to touch the water. The city is to the east (left) and the crypt is to the west (right).

In the city district, you need to open the door to the inner city. Solve the Nedic Pillar puzzle by looking at the lighted pillars ( from left to right: face, serpent, dragon). Continue through the inner city to the upper northeastern corner, where the water is on the map. Defeat Jah'lah. Reflecting her poison attacks works well.

In the crypt district, defeat Emi'liah. She is in a recessed area filled with poisonous water. Be careful not to jump in it, instead use the stairs and wooden ladder (or jump onto the rocks and clean water) on the right. Look for the spots above the water, like the rocks, or patches of dirt you could use as a safe zone. Go up the stairs on the north side for a quick exit.

Once you have cleansed both districts, you return to the area where you met Sali'ma. The researchers have gathered at the city and crypt junction. Tell Sali'ma he was right about the nereids. He deciphered writing in the city: according to it, Shada "blessed" the waters, so the city could defend itself from invaders. He guesses that Shada is in the temple wing, where the people of the city worshipped her. You must find and defeat her.
The Queen of the Nereids
Swim across the now clear water. Shada appears at the top of the stairs and addresses you.
:"Murderer! Slaughterer of innocents! These people are under my protection! I alone gave them hope! I alone gave them a future! Leave now and I will spare you. Enter and your fate will be the same as the Yokudans before you!"—Shada

Enter the Hall of Worship. As you make your way to Shada's Chambers, she offers you promises of power, just like her thralls. On your way, you face (the entirely optional) Muhma the Stinger and other spiders, then more Nedes and nereids. In the final area, you face off against the queen of the nereids herself. She summons shield maidens, nereids with healing powers to heal herself. After defeating them and attacking her a little more, she summons Nedic mages to each of the four stone slabs.  

When you've defeated Shada, return to Sali'ma. The door back to the main area lets you out on a natural ledge. Jump down into the pool of water and swim over to him.

The enthralled researchers are no longer under her spell. He hopes your hard work will allow them to properly research the city, and gives you a reward.

Notes
Each wing of the fallen city, except for the temple wing, has its own quest (City District: Waters Run Foul, Crypt District: The Reason We Fight). Although these do not influence the outcome of The Fallen City of Shada, you might want to complete these while you proceed through the respective areas.
Fighting Muhma is entirely optional.
 

Quest Stages