I was playing dungeons deep and caverns dim with a friend and we completed stage 2 by answering a riddle corretly two cards into the four we needed to draw for the staging step. Stage 1 already had enough progress to advance so we moved on to stage 3 and activated its when revealed effect. But now we were on a different stage and the rule to reveal an additional encounter card per player was gone and replaced by one where trechery cards gain surge. So wht should we have done? Does the staging step and or quest phase end when you change stages? Or should we have now revealed one more card (instead of two but adding surge to trecheries) for the second player's part of the staging step and then applied progress to the new quest stage?

I've had that happen and I resolved both effects. So reveal an extra encounter card, and if any treacheries come out, give them Surge.

My reasoning is that the number of encounter cards to be revealed during the staging step is determined at the beginning of the staging step, and does not decrease if one player is eliminated during staging (per the FAQ). I extended that logic to this situation, so the number of encounter cards to be revealed is fixed, and won't change even if you advance to the next stage of the quest. As for the Surge part, as soon as the final stage of the quest comes into play, its text becomes active, and so any treacheries revealed after that point should get Surge.

And yes, you would apply any progress earned to the currently revealed stage of the quest (the final stage).

Awesome, thanks for that. We did the same as you, I thought at least if we did it wrong it was a hinderance rather than an advntage to us, so its not cheating. But based on what you said I think we did it right. Cheers!