And there is a compromise plan... one that uses the best of both.  Start the positive energy ritual, 7 hours in, the team goes into the Lab and tries to do plan A.  If they fail, they retreat to the surface and try to hold the exits until Plan B finishes.<br/><br/>Oh, and using the hallow will probably start a mass exodous of Undead.  We want to be in place defending the exits if that happens.