Quote Originally Posted by Unregistered View Post
What 'mission' would be quickest to play through, so that I can get fast those event things.
You can do it all on one-crown missions. I know this isn't actually answering your question, because I don't know what's 'most efficient' either. But I'm 3 EPs away from earning the second-to-last event reward and that's all I've been running. I haven't bothered to try to run the higher missions...the thunder rewards are probably higher in them, but in some games it isn't worth the 'stamina' cost (in our game, crowns) to do more than grind the lowest mission multiple times. Since my way works, I've just been doing it that way without worrying about what else I could do. But since we can get nymph shells in addition to EPs, it might be good to know how to max out the thunders.

Also, in case anyone doesn't already know, watch for thunders popping out on the grid after you complete a mission. These are separate from the mission rewards and can give additional event points if you click on them before the mission end dialogue screen comes up.