The drill was already underway when Batu reached the rise.

Two mingans were on the flat ground below, one from Torghul’s tumen, one from Orda’s White Horde, working a coordination exercise across the open ground north of Sarai.

The winter air was still and the cold precise, and the horses’ breath came up in white mist from both formations. Penk’s relay rider stood at Torghul’s coordination point on the left. Orda’s formation had its own riders at position but no equivalent auxiliary at the coordination point.

Torghul was already on the rise when Batu arrived. Orda stood beside him with his arms at his sides, watching the drill with the attention of who had identified the problem and was waiting to see it confirmed. Tangqut was closer to them. Toqa-Timur a few steps behind. Berke stood at the outer edge of the group, slightly apart, as was his habit.

The relay signal went out from Penk’s point to Torghul’s mingan on the left. The formation responded immediately, the leftmost riders adjusting their spacing, the signal working through the ranks before the interval had completed its cycle. Then the cross-formation rider moved out, carrying the same signal toward Orda’s mingan on the right.

Orda’s formation held. The riders were in their positions, but nothing moved. They were waiting for direction from their own commander, not from an unfamiliar rider arriving with an unfamiliar motion.

The difference that opened between the two formations, Torghul’s moving and Orda’s stationary, was visible from the rise before anyone on it had said a word.

Nobody spoke for a moment. The drill kept running on the ground below, both formations holding in the broken coordination.

Torghul was the first to speak, and he did it without looking away from the ground below.

"The unfamiliarity with the system is a problem," he said.

Orda said. His voice was even. He wasn’t defending anything. "It’s not a performance failure. The signal meant something different to them."

Batu looked at the two mingans still holding below.

"What would standardizing the doctrine actually require."

Torghul considered it. "It’s winter work. There are fewer than twenty signals that matter for coordination, movement, halt, tighten, spread, relay received. The arm movements are memorizable. A rider can be shown the signals in a day and be doing them correctly within a week. If every mingan puts its relay riders through the same demonstration before spring, the doctrine becomes standard." 𝒇𝙧𝙚𝓮𝙬𝙚𝓫𝒏𝓸𝓿𝓮𝒍.𝓬𝙤𝓶

"The timing interval stays local," Batu said.

"Yes. Each formation sets its own based on its spacing. Only the signals are common."

Orda looked at the ground below for a moment. "My formation can accommodate the standardization."

His voice became more stiff. "What I won’t accept is the evaluation criteria applied retroactively to my existing command structure. My commanders earned their positions through demonstrated performance in the field. I’m not asking them to sit for a written standard to keep what they’ve already proven."

Batu pondered if it was worth the friction to force it, and decided against it. "The White Horde existing commanders can keep their positions. New promotions in any Jochid formation go through the written standard from this point forward."

Orda received that.

"That I can accept."

Tangqut had been watching the formations below with the look he used when he was working through the practical end of something.

"What does training this actually look like in a mingan that’s never run the relay," he said. "My riders haven’t done it. What does a training day for this look like."

Torghul turned toward him.

"One month for the signal vocabulary, they’re running it correctly by then. Two months for the relay rider auxiliary to be reliable at the coordination level. You don’t run both at once. You start with the signals and add the relay after the signals are solid."

"And the interval."

"You set it based on your formation’s march spacing. The only thing that has to match mine is what the signals mean."

Toqa-Timur had been listening with the steady attention of who wasn’t going to argue but wanted to understand the full scope.

"What about the mingans that operate in hilly countryside," he said. "If the territory runs into the Caucasus mountains, what does the signal system actually do in that terrain."

Berke was looking at the formations below, and he spoke without turning toward the group.

"The system breaks in enclosed terrain," he said. "I was in the reed channels, and the arm signals don’t carry through reed walls. In city streets they carry through one block and not the next."

Nobody argued with him.

"So you know when it works and you know the conditions where it doesn’t," Batu said. "The backup for enclosed terrain is what it was, route markers, fixed positions, direct rider contact. The relay is for open ground for now."

"That’s already the doctrine," Torghul said.

"Then write it into the expansion. The relay protocol applies in open conditions. Enclosed terrain procedures are a separate section."

The second run of the drill had started on the ground below. This time the cross-formation rider was using the simplified vocabulary that Torghul’s coordination rider had demonstrated for Orda’s mingan beforehand, a single agreed signal for the purpose of this exercise.

Orda’s formation responded when the rider arrived. A beat slow compared to Torghul’s, the unfamiliar rhythm still working itself into the formation’s timing, but the response came and held.

"One month," Orda said, watching his formation move. "That’s what it took to get them to respond to a foreign signal at all."

"The second month is the difference between responding and responding correctly," Torghul said.

Orda watched for another moment and then turned back to the group.

"The doctrine standardization, the between-tumen relay doctrine, the forward-only evaluation standard. Those are the three pieces."

"Yes," Batu said.

"Penk runs the demonstration for any mingan that needs it," Torghul said. "He can cover the White Horde and the Jochid’ contingents before the month is out if we start this week."

Tangqut said, "That works."

Berke had returned to watching the formations below, his contribution made and nothing more to add. Toqa-Timur looked at the two mingans coordinating in the cold with the satisfied attention of a man watching something work that he’d had reasonable doubts about.

The second run finished and the formations stood down. The riders’ breath rose in white mist in the still air and the formations began breaking into their separate positions.

The commanders dispersed back toward their sections. Orda went north toward the White Horde’s area of the camp. Torghul went south to find Penk. Tangqut and Toqa-Timur drifted together in the way of men going in the same general direction with no reason not to. Berke walked east on his own.

Batu turned south, away from the drill ground. The Khar Kheshig section was at the camp’s south, a stretch of open ground between it and the main formation areas. He walked toward it.

The camp sounds were behind him, the formations still sorting from the drill, horses moving on the lines, the low noise of a winter camp in the middle of its afternoon.

He came through the outskirts of the Khar Kheshig section as Suuqai was organizing the two halves for their own exercise. Suuqai looked at him once when he arrived and did not change what he was doing. Batu stopped to watch. He was there for the conversation he needed to have before the week was out.