Victory From Within

A few of our men didn't make it through portals which were supposed to open inside this very abbey. You've already proven your elusiveness and battlehardiness... now I need you to do so again. The abbey has two wings: a library, and a hall of arms. In each wing, you should find a portal. Use this keystone on these portals. Doing so should force them open, allowing our remaining shock troopers to take this abbey.