Below is a guide on the Basement Burners dungeon. You can access this area during The Burners quest!
After you unlock the door to the basement of the Blacksmith’s building, defeat the rats then use your fire to light all 4 braziers.
You’ll then be able to proceed through the next door. In this room you’ll need to defeat the mice plus the spider. The problem is that the floor boards will break if you step on them more than one time. After you defeat them, the door on the west side will unlock. Head through it. Again, defeat the mice and the spider. This time a chest will drop containing a Dungeon Key! Head through the eastern door to arrive in a room with red spiders. Throw an object at them then strike them. Be careful as they will blow up when they die. Defeating them will cause the fire to ignite.
Backtrack to the room with the floorboards that break. Head through the southeastern door. Defeat the mice in this room. Head through the door on the northeastern side. In this room defeat the mice and spider then dig up the dirt patch on the western side of the room to find a Dungeon Key. Continue pressing forward through the door on the northeastern side. Head through the door on the western side then unlock the door in the next room. Defeat the large enemy inside by striking it. It’ll blow up when it does and most likely kill you in the process, but that is ok! After it’s been defeated, turn the levers to where they are both pointing southeast.
Backtrack to the brightly lit room then head through the southeastern door. Defeat the rats then burn the web to continue forward. After you head through the door, you’ll need to defeat 2 red spiders. You must throw the pots at them first to knock them back then strike them with your sword. Be careful when they die because they will explode. Before you leave, you can dig up 10 Dindi in the middle of the room.
Backtrack to the room with the breakable floor and head through the western door. Make your way all the way to the locked door and use the key to unlock it. This will bring you to a room with grates as the floor.
Inch your way super slowly through this room so you can see where the steam comes up, preventing you from going that way. Make your way all the way around the room to the door on the western side. Turn the lever so it points southeast then push the thing into the burner.