User blog comment:LordLuminous/Fairy Tail Chapter 411 Theories and Predictions/@comment-96.24.244.24-20141128160046

I think the next chapter will deal with Lucy and Lumen Histiore. I feel like you have to be around LH for it to take affect because if you didn't I don't see why Makarov would need the group to come down to the basement. It is a reason why Makarov told them to come back to the guild because if LH had a long range he would have already released it and defeated tartarous. Also I doubt it helped Erza out as Mirajane, happy and Pantherlily would have felt it's power if LH had a long range as all of them posses the same guild mark as Erza.

When I think of Quid pro Quo I think of Lucy sacrificing Aquarius's Key in exchange for summoning the Celestial spirit King. For LH to be releases something needs to be given up in order to awaken Mavis.