User blog comment:Xkisanagi/Holy EH rewards Batman!/@comment-112.198.133.97-20160330142849/@comment-27652489-20160401175334

EH lasts for a total of 6-7 days or so, right? So if you got 60, you'd want to spend perhaps 10 keys a day; nice and equal. That's definitely sufficient.

Let's say you do Advance hall: 4 battles, & we'll round to 100k pts per battle. 1 round (4 battles) = 400k pts. Say you get 3 rounds out of 1 key: 400k * 3 = 1.2m pts. 10 keys gets you 12m pts. 2 rounds, same formula: 8m pts. Worst case scenario, you only get 1 round per key; same formula nets you 4m pts for 10 keys.

^ That's pretty good if you're doing EH for ranking and want to stay above T2000.

Or, maybe rushing all 60 keys on a passion day for the awakening material.

I don't know why I did the math for that.