Quote Originally Posted by Blaxer View Post
Yeah 90/12 maps are like that, better drop rates at the cost of possibly wasting a lot of STA; lesser maps (Pumpking King in this case) have worse drop rates but in the worst scenario you waste 7 STA instead of 12 which is almost double
It's been my experience with both revivals and the original events that the 80/9 maps are quite decent to farm as well. They don't give as much as the 90/12 but for those that can't do the last maps it's a good option.

The only downside is that there is no way to get a perfected unit without spending a great deal of SCs, certainly more than for a 90/12 map. However you could comfortably get 600-700 items which can give a -3 cost and a level 6 skill. A nice deal I think.