There will be three different times when you’ll want to locate the Dung Eater in Elden Ring. To find him for the first time, you’ll need to go to the Roundtable Hold and speak to both Roderika and Blacksmith Hewg across various visits.
You must undergo these continuous visits up until Roderika becomes a Spirit Tuner who can upgrade your Spirit Ashes. At one point, Roderika will have the “There’s something you should know” dialogue option, where she explains that she can hear cursed voices from the other side of the Hold.
You can now progress beyond the Twin Maiden Husks on the other side of the Hold to find the Dung Eater sitting, surrounded by corpses, in a newly opened room. The Dung Eater will wish for you not to disturb him.
This will continue until you get your hands on your first Seedbed Curse (more about this below). Return to him after procuring your first Seedbed Curse, and he will tell you to go find his true corporeal form in the sewers under the Capital, Leyndell. He’ll give you the Sewer-Gaol Key to aid in your journey.
Here are the two locations of the Dung Eater:
1. Dung Eater Capital Sewers Location
You can get to the Dung Eater through the capital sewer location by heading through the sewers of Leyndell until you reach the ladder which brings you up to the tip of the giant dragon’s wing. Now head down the stairs across to the west until you reach a wall that you can jump over on the left. This will lead you up a slope and into some ruins.
Continue heading into the town area, and drop down the well that you’ll find there. Follow this path through the new area known as the Subterranean Shunning-Grounds, and you’ll reach the Dung Eater’s location in his Sewer-Gaol.
2. Dung Eater Invasion Location
If you decide to free the Dung Eater, then he will disappear. Upon returning to his previous location in the Roundtable Hold, a note will be left for you, telling you to meet him for a fight at the outer moat of Leyndell. To find the new location of the Dung Eater, follow the map below. If you go here, then the Dung Eater will invade your world and fight you.
After defeating him, you’ll be able to speak to him at the Roundtable Hold, where he tells you to give his corporeal body under the Capital more Seedbed Curses that you find.
That’s how you can get to the Dung Eater in Elden Ring on Steam Deck.