This Portal Keystone opens gateways to far off places. There's no telling where it goes, but it seems likely Chekharoth would make use of such an artifact. Perhaps Chekharoth, or a clue to his whereabouts, is just beyond one of these portal destinations.
I have had most of my men out in that blasted snow searching for Chekharoth, and yet it appears he was often here under my very nose thanks to those blasted portals! And now he has slipped my grasp once more. We must put an end to this traitor, [%NAME]!