Izetta is powerful enough to fight whole armies, but her strength is limited.  She can only use her abilities near certain ley lines, and outside them, she's no different than a normal girl. When the Germanian army attacks in a spot far from these ley lines, the duchy is forced into a corner: how can they repel these foes without giving up the secret of Izetta's strength?
that was blockading 
Bristlich near Ruden Lake.
التي كانَتْ تُحاصر بريستليتش قُربَ بُحيرة رودين
que bloqueaba Bristlich,
cerca del Lago Ruden.
que bloqueaba Bristlich,
cerca del Lago Ruden.
qui quadrillait Bristlich,
au bord du lac Ruden.
attualmente impegnata in un blocco su Bristlich,
sulla riva del lago Ruden!
que estava bloqueando 
Bristlich perto do lago Ruden.