Sten Revna was no stranger to the dreaded whistle of artillery, but it had been sixteen years since he had heard them. It made him anxious, even this far underground. Artillery was a horrible thing. It frightened the ever living warp out of soldiers, but there was never anything they could do about it except hope and pray it didn't hit them. It frakked with men's minds and they often lost it for no reason. Artillery was one of the things Sten missed the least about the Guard.

He proceeded through the base towards the Auxiliary Command Center casting his mind out ahead of him to determine the best possible route through the bastion. A lit lho-stick was clenched between his lips, filling the corridors with its lingering and distinctive scent. One or two officers along the way tried to get him to put it out, but were silenced by the inquisitorial electoo on his hand. Sten was in no mood for patience, and neither was his master. 

Sten had spent the last four years in the employ of Inquisitor Xersus, who had recruited him not long after he had earned his Primaris rating. He hadn't been brought along on very many missions, but was regularly employed for his precognition. Sten respected the Inquisitor greatly: Xersus bore the twin responsibilities of a psyker and an Inquisitor and he met them with a will more dauntless and hardened than any man Sten knew. 

Sten's mind felt the presence of his master, and he homed in on it, following it like a beacon. He doused the tiny ember within his lho-stick and returned it to his case before he reached the command center. He entered without knocking, for Xersus surely sensed his presence as well, and bowed. “Inquisitor.”