Conspiring Against Yazdegerd

Sarus sat in a room alone with Marcellus. He had rushed back to the capital of the Western Roman Empire after receiving a summons from the Imperator himself. The two men were drinking wine as they discussed a devious plot to assassinate one of Marcellus' rivals. Marcellus drank the whole contents of his chalice before speaking of his sinister plan. 

I summoned you here, because I need to know if you have any contacts within the Germanic tribes who still exist outside my borders. I won't lie to you, I have an opportunity to eliminate one of my rivals, and improve relations with the eastern roman empire. However, should this attempt to fail, I can't have it traced back to me. You understand, don't you?"