is it possible to use cards from expansion in the base set quest?

in general, is it possible to use newr card in older quests?

yes in this game all cards from new expansions can be used in older quests. the only time cards cannot be used are:

- when a quests says you cannot (i cannot think of any right now, though when a quest has an objective version of an ally card in play throughout the entire quest, that is basically the same as saying you cannot use them, though you could still include them in your deck)

- saga pack heroes and hero sphere cards

rich

Treasure cards can only be earned.