I got the perfect score on PtM yesterday - 0 threat, Hummerhorns (-5), Chieftan (-4)
The tactic has been discussed before, but was playing with a Lore/Spirit deck of Berevor, Glorfindal and Eowyn.
Using Henmarth Riversong every turn you can perfectly guage your questing so that you don't make progress on the last quest card (I had Beorn's Path) , enabling you to hang around indefinitely.
With Unexpected Courage on Berevor, plus Gleowine, card draw was very high, with nearly all my deck in hand or in play towards the end. Galadrim's Greeting, plus Gandalf to lower threat, Dwarven Tomb to recycle Galadrim's, and finally 3 x Will of the West to recycle the deck indefinitely.
With such a small amount of cards actually left in the discard pile at the end, recycling with Will of the West puts Galadrim's greeting and Gandalf back into your deck nearly straight away.
Hummerhorns was taken care of promptly by Gandalf, but I had to go through the encounter deck three times before drawing the Chieftan as an enemy and not a shadow card. After offing him I quested to victory with 0 threat. :-)
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