I'm just a little confused about Lieutenant encounters and treachery. I know that if I have used exp. to get treachery and bought cards with said treachery, I can add them to my base deck (with appropriate swap-outs).
In a lieutenant encounter, do I :
1) Get to pick those cards out of my OL deck and use them or
2) Use unspent treachery and purchase them out of my OL deck/unbought treachery deck?
If 2 ) is the case, since you only get a set amount of each treachery, why would you waste treachery (which are quite expensive) on one-offs with lieutenant encounters instead of purchasing them for your OL deck and getting the chance to use them every dungeon?