Biggest problem with lightning bosses are that only the players who summoned lighting boss and the player who got last hit get any kill count and rewards.

At japanees all players who did dammage to a lightning boss get rewards and and kill count!!!

I group af 20 strong players can take down a small lightning boss together - but what is the point of a group if it is only the whale that get the kill count and the rewards!!!

I been playeing for like 4 weeks at Japanees servers and I am total free player. I got 200 lightning boss kills last Sauterday and amasing rewards it was really cool. My base SED is only like 400-500k and I only got N-slayer girl at that server. To do lightning boss you ned strong friends and problem is that there are not many level 150 - 200 players on our server.
Even if you team up with the top 2 strong players here and kill lots of lightning bosses - players like myself are left with nothing more than a few EP.

People cryed we hate 8.7 M bosses - I and the remowed tha cap so bosses cound got more power that 8.7M
People cryed we want a slayer N-girl and we got the new set of slayer girls early (Remenber there are newer more than one slayer girl of free players).
So developers give players what they ask for but maybe not what the players want....