Valley drops vary. However a month or two or grinding away will get you near the top.
Wisdom Medals are the hardest to harvest I have found.
Somedays a valley will drop on every hit. KurChingaah !!!
See my previous for some attack packages that work for me.
If you want to be fussy, cut your troops by 500 each hit until you just start losing a few then go up that last 500. It appears that being close makes medal drop better but I am not sure on this.
http://bbs.evony.com/showpost.php?p=1838348&postcount=4


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