The Sewer Key is found amongst the items carried by Tazok and can be discovered as early as Baldur's Gate II Chapter 2.
Location[]
It is dropped by Tazok at the end of the second level of the Windspear Hills dungeon. Precisely why it is located so far away from the door it serves to open is a mystery.
Description[]
| “ | This key has a faint but foul odor clinging to it, like that of the sewers. There are no sewers within the halls where you found the key. The lock that this key opens will have to be found elsewhere. | ” |
Gameplay[]
The only clue as to what this key may open, is in the description for the key, and of course, it's title.
A "spoiler" reveal button is below for readers who want to know the answer to this key. Don't read it if you desire to figure it out on your own as intended for a first time player.
[ Reveal What's the Key for? ]
[ Collapse What's the key for? ]
The key will open the secret wall panel on the NE corridor of the Sewers (Temple District).