Time left
Subject Time
From the time the prayer was cast till the time the party got back out to the main room I would say that a total of 5-10 minutes would have passed. The party has no real good way to tell the passage of time. Depending on how fast they get back into combat the Magic Circle should still be good for at least another 1/2 to 3/4 of an hour.
From: Jason
Subject Undead
Its a good thing Harp isn't as knowlegeable as his player is, or a lot of us would have been a lot more worried about that fight. I had no idea either.
IC: "I'm not entirely sure. It was definitely an undead creature, and I have heard that some of those can drain the health out of a man, leaving him sickly unless he receives powerful divine blessings. I'm sure we can all feel greatful that Heironeous has watched over us this day."