In the rule book, I found that the keyword "surge" is explained like"when an encounter card with the surge keyword is revealed during the staging step of the quest phase, reveal 1 additional card from the encounter deck . Resolve the surge keyword immediately after resolving any when revealed effects on the card."
So I wonder if we need to add the card been revealed by the surge keyword into the staging area? or just trigger its keyword and "when revealed" effect and put it back to the encounter deck? because it doesn't say "reveal and add into the staging area".