According to the Book of Answers for A5, under Tranquility Quests, Solberg's Tower, the first quest listed is South Tower Sentinel. To kill it you start off with melee, then fire, acid, poison, repel spirit and finish it off with magical energy.
My problem is I didn't finish it off fast enough for Tia so she said go back and do it again. Problem number 1 it's not there! Problem number 2 maybe it's because I didn't have any poison???
that I couldn't kill it.
Regardless, from this thread, I can see there's more at stake than just the sentinels! Hope someone comes up with the solutions.....