Is "Explore Dark Caves" part of any quest line?

[trailbean]

Preparing for "Explore Dark Caves" adventure is a bit expensive, or at least time-consuming. Now that I have both Spicy Feat and 2 Lumin Essences -- should I go ahead and do the adventure, or save it for some future quest?

[burritosprings]

Part of the Thurston line


http://forums.storm8.com/showthread.php?41844-Castle-story-Goals/page6

I think that's the first time its needed but maybe someone can verify


18. Secrets of Methril .Rewards 800 coin 3xp
. SEND Knights to Explore The Dark Caves (Adventure from Castle
1 day: 1 Spicy Feast. 2 Lumin Essence. 5000 coin
. ACQUIRE 1 Mithril (thru adventure or other *means)
*usually 1st time on this adventure, the knights bring back the Mithril

Notes: Mithril: mining deep mine or rare Sir Piggy drop or Magic Forge if you have completed the goal for the 4th Shard (Tablet of Tabernum)