Travel to Gamlen's House in Lowtown and read the note on Gamlen's table. Speak with him, and he will tell Hawke to pipe out of his business. The note talked of a gem that Gamlen had been pursuing; head to Darktown and meet with Mekel who apparently sent it. He will demand the gem and Hawke will have to fight him. Loot the corpse to discover a note referring to Gamlen's Wallop Mallet. A member of your party will mention that Gamlen had a Wallop Mallet on his wall; return to Gamlen's House and speak with him before examining the mallet.
To continue the quest, travel to the Elven Alienage in Lowtown during the day and examine the sacred tree which the mallet was carved from. An elf will overhear you and your party discussing the Wallop Mallet and present you with yet another note, this time speaking of a crate in a Fish Guttery.
The final location mentioned is the Sink. Travel to the location and fight your way through a few undead and Giant Spiders until you reach a woman who reveals herself to be Gamlen's daughter, Charade. Before Hawke can discover more about Charade, Veld interrupts claiming that Hawke killed his brother, Mekel. He and his men will fight Hawke before you can speak with Charade again.
When the battle is over, she will tell Hawke that her mother left Gamlen before she was born, and that Gamlen had no idea her mother was pregnant. She will also say that the reason her mother left was because Gamlen had been completely obsessed with finding The Gem Of Keroshek and Charade wanted to know how far he would go to retrieve it. Depending on your dialogue choices, Hawke will either encourage or dissuade Charade to meet her estranged father or demand the gem from her.
Either way, the quest will update for you to return to Gamlen's house. There you will find Charade talking to Gamlen if you had encouraged her to meet him otherwise you will visit him to show him the gem. In the first case Gamlen would thank you for bringing him his daughter but also warn you to not get involved in his business anymore and in the second case he will comment that he expected the gem to be better and doesn't want it. In that case you can either tell him about Charade or not.
If Hawke decides to encourage Charade to meet her estranged father, she will send Hawke a letter explaining how she and Gamlen are getting on.
- Demanding the Gem of Keroshek results in
(Note that upon returning it to Gamlen you will get +5 Approval from Sebastian, nullifying the rivalry gained.)
When conferring with Charade, demanding the gem (otherwise nothing - no money nor XP in either case):
- Gem of Keroshek
Enemies drop more coin
- If you do not speak to Gamlen after reading the note, the quest will say to go to Darktown; but there is nothing to do there. You need to go back and speak to Gamlen if this happens.
- There seems to be a glitch to where the mercenary captain's corpse does not appear. If this happens, the only known resolution is to load an earlier save. Another resolution is to use the console command "runscript zz_dae_debug" and use the Plot Jump option to jump to the warehouse directly after the encounter with Mekel. The exact path is, "Plot Jump, Secondary, One Offs, Work With a Plot, Investigate, Gamlen's Greatest Treasure, Plot Jump, Warehouse". This will make the game behave as if you were able to loot Mekel's corpse for the letter and have traveled to the warehouse in search of a missing crate.
- When seeking Charade in the cave, sometimes the stone door entrance to a corridor does not allow you to open it. Just finish some other quests and return later.
- Dialogue during this quest makes it seem that Hawke has no idea what a wallop mallet is, even though they can make a reference to the game of wallop during a conversation with Anders in Act 2.
- On Xbox360 there is a trap near crate 1309 behind some other crates and therefore not reachable.
- When you talk to Gamlen about his wallop mallet, he'll claim he hasn't played since he was a kid. However, during The Destruction of Lothering, Meeran explains that Gamlen cheated one of his men at a wallop match. This is either an oversight in the dialogue, a lie (or oversight) by one of the characters, or Meeran had been holding a grudge over this wallop match for many, many years. Or more likely, Gamlen's cheating involved betting rather than actually playing wallop.
- After killing the mercenaries in Smetty's Fish Guttery, Hawke says "It's time to end this charade," unknowingly naming Gamlen's daughter, Charade.