Approximate worth of 1st dark lord crystals

Good evening,

I'm new to the game and trying to gain those first few Ep to begin trading. I found that one of the ways was to farm out dark lord crystals from the first two missions.

My question is: What are they worth? For example: how many dark lord crystals would trade for an EP?

I'm still new to the game so any help is much appreciated.

Thanks,

15:1 ep, for any of the first 3 dark lord crystals.

Thanks! That actually leads me into another question I had:

Are crystals from higher missions worth more/ do they give better prizes?

They're not worth the energy needed to farm them. Only a few lords are worth getting silvery goddess queen, fortress engine, dragonlord of hellfire come to mind

Thank you for you help!