Explore the dark caves worth it?

[freshpickins]

I made two nice spicy feast and realized that the lumin essence requires so many earth wisps. Can you guys who have done the adventure tell me f it's worth it? I'm pretty happy with the bandits so far, and I know the simple feast doesn't give much. Any thoughts?

Edit: gems, dark cave formation, wisps, lanterns, silver, apple tree, lemon tree, enchanted beam, enchanted block, super glue, Glimmerdust, black cow, mithril, pig, unicorn statue, dragon statue, beast statue, builders paste, black sheep, royal pig, royal cow, orange tree, white cow, sheep, alicorn wing, alicorn horn, coins