Dampened Spirits

After completing the quest "Loud and Clear", Brynjolf will say that Maven Black-Briar wishes to speak to the Dragonborn.

Objectives

 * Speak to Maven Black-Briar
 * Speak to Mallus Maccius
 * Speak to Sabjorn
 * Poison the nest
 * Poison the Honningbrew vat
 * Attend the tasting ceremony
 * Identify Sabjorn's silent partner
 * Return to Maven Black-Briar
 * Return to Brynjolf

Walkthrough
The first step in the quest is to speak with Maven Black-Briar. She will be waiting upstairs in The Bee and Barb or in the Black-Briar Meadery in Riften. She asks the Dragonborn to shut down a competitor, newly opened Honningbrew Meadery, and to find out how its owner Sabjorn has managed so quickly to fund its opening.

Next, it is necessary to find and speak with Mallus Maccius. He will be waiting in The Bannered Mare in Whiterun. He tells the Dragonborn to ask Sabjorn for work clearing out pests that Mallus has lured into the meadery. The Dragonborn is to fulfill this job, poisoning the meadery vat in the process.

Sabjorn will give the Dragonborn a key to the meadery's basement with instructions to kill all the pests and to poison their nest. This presents the opportunity to poison the vats as well. Getting to the nest is straightforward, but there are quite a few skeevers and some frostbite spiders along the way. However, the real challenge is dealing with Hamelyn; a mage living next to the nest. He uses a fairly powerful magic attack (which appears to be random, but may vary depending on the Dragonborn's race). If the Dragonborn is a werewolf, transforming may be a good option: growling will cause him to enter a state of 'fear', offering an excellent chance to kill him.

Sneaking past Hamelyn is also a possibility, by shooting an arrow down the tunnel to the left of his alchemy lab. When he moves to investigate, the nest can be poisoned quickly, and then the Dragonborn can retreat and wait for him to return. After that, it is possible to go around him and enter the tunnel.

The area to poison the nest is the pile of hay to the right of the alchemy lab. The area where poison can be used is fairly small.

Going through the tunnel to the Honningbrew Boilery, it is possible to go up the stairs and pour the poison into the vat. The door's key hangs right next to it. Afterwards, Sabjorn needs to be told that the job is done.

Now it is time to attend the tasting ceremony. Commander Caius or Sinmir tastes the mead (depending on the Dragonborn's Civil War allegiance) and is unhappy with it. He puts Mallus in charge and drags Sabjorn off to Dragonsreach Dungeon.

At this point, Mallus will help locate the books that identify Sabjorn's 'silent partner'. Upstairs, a promissory note is in Sabjorn's dresser. Behind the door to the right of the dresser is the Honningbrew Decanter (a larceny target), which can be sold to Delvin Mallory.

Upon returning to Riften, Maven Black-Briar can be given the note. She tells the Dragonborn to take the information to Brynjolf, who acknowledges the findings and sends the Dragonborn to Mercer Frey (who he feels will be able to identify the symbol on the note and shed some light on the Thieves Guild's anonymous adversary). The quest "Scoundrel's Folly" then begins.

Rewards
Upon returning to Maven Black-Briar, the Dragonborn is given either a leveled enchanted dagger, sword, or Mace and Mallus will become available as a fence.

Trivia

 * When going to Sabjorn's room in his office to collect his notes, under his bed in a bedpan, one will find a bottle of Black-Briar Mead.
 * On Sabjorn's desk, there is a note from Maven Black-Briar regarding his meadery. It can be assumed from the note that Maven has repeatedly tried to buy Honningbrew from Sabjorn without success.
 * If Serana is brought into the Meadery after completing the quest, she will occasionally approach the barrel Caius drank from, pour herself and drink an invisible goblet of mead from it. She may also do so during the quest, stalling the quest indefinitely until the player moves away or tells her to do something.
 * Caius will always appear for the tasting, even if the quest Battle for Whiterun, on the Stormcloak side, is completed, and Sinmir replaces him.

Bugs
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