Dear Gree,
Are you aware that the boss event difficulty nearly doubled between the last epic boss event and this one? In the last epic boss event, the level 100 boss had approximately 700 million health. In the current epic boss event, the level 100 boss has approximately 1.3 billion health!
This completely negates any advantage we might have gained in the interim period between events from attack stat increases and epic boss damage modifiers. And then some.
What incentive is there to increase our stats and earn bonuses, when you inflate event difficulty at such a rapid pace? How about you slow down a little bit and let the players catch up?
In addition to being unfair and exceptionally selfish on Gree's part, these types of events are already out of reach for free to moderate gem players. The current pace at which you are inflating event difficulty will drive away heavy gem spenders as well.
As I have said many times in previous posts, you need to increase event difficulty at a rate where your AVERAGE player can keep up by playing an AVERAGE amount of time and spending an AVERAGE amount of gems. Your events are currently scaling at a rate where not even your top spenders can keep up.
I suggest you take my advice and pass this feedback along to development. I love this game and am trying to help you stop destroying it.