To be fair, Yotanwa is comparing them not to her own faction that consists of numerous tribes but rather the individual tribes she had fought or was fighting at the time such as the Mera and the Feego, who individually would not match a Xiongnu force but united under Yotanwa, they would.
I would actually say that the Ryuudou is exactly the kind of formation that the Mountain Warriors would overcome through sheer strength.
The Ryuudou has only ever worked for a defending army that is significantly larger than the force attacking it.
100,000 Wei Ryuudou vs 10,000 or less Qin assault. The Wei force is 10x larger.
40,000 Zhao Ryuudou vs 5000 Qin assault. The Zhao force is 8x larger.
The Ryuudou has also only ever been used to redirect the attack of a single wedge formation charge.
In my opinion, the Ryuudou cannot deal with either multiple large scale attacks simultaneously (e.g. if any combination of Yotanwa, Katari, Kitari, Danto, Bajio and even Shunmen attack in sync) or with an assault force equal or nearly equal to the defending army.
It also only works when the attacker is specifically aiming for the defender’s headquarters and also if the attackers fight as a unit.
What would likely happen here is that instead of a Mountain Warrior unit being split up by a clump of Zhao soldiers, a few mountain mad lads would jump straight at that clump, open the formation up and allow everyone else to slaughter some Zhao and then move on the enemy headquarters anyway.
Mountain Warriors produce individuals that lay on the ground after being hit by crossbow bolts so that they can disrupt and open up an enemy formation and charge at retreating Zhao soldiers going through a gate just to have first blood.
Mountain Warriors are legit mad lads on the individual level. Trying to separate them on a unit level is not going to work.
You have either never read Kingdom at all or have never gotten past Chapter 20 of Kingdom, have you?
The strategic mastermind behind the actions of the Zhao forces in the Battle of Ryuuyuuwas not anyone from the “simple minded Dog People” but Shunsuiji, Riboku’s left hand man and his greatest subordinate in terms of strategic prowess, who Yotanwa outright outsmarted by using herself as bait, luring the Quanrong King Rozo and his main force out and taking the relatively unguarded city right from everyone’s noses.
The mountain people overcame the odds specifically because Yotanwa is a great strategist who can come up with a workable plan quickly, under great pressure.
To be fair, he outmaneuvered Ouki due to Ouki (or anyone outside of Zhao for that matter) not even being aware of his existence.
Despite this, Ouki still correctly predicted the existence of Riboku’s Army and that his army would arrive with the intent of trapping him. He only miscalculated the speed of Riboku’s Army. Riboku basically won out on a technicality.
Besides, if we count that as Riboku outsmarting Ouki then Yotanwa has canonically already outsmarted Riboku during the Battle of Sai.
I believe Yotanwa is being heavily underrated in this thread.
Riboku, in my rankings, would naturally be among the absolute top of the highest possible tier in my ranking list, the “Greatest Tactician” tier. Yotanwa would at minimum be in the upper end of the tier below Riboku, the “Master Tactician” tier. At best, she would be at the lower end of the same tier as Riboku.
Now one might think this naturally gives Riboku the strategic/tactical advantage over Yotanwa. However, there is a problem for Riboku here.
Riboku’s tactics and strategies are designed to deal with traditional Chinese armies or the cavalry oriented Xiongnu. They are not designed to deal with Yotanwa and her completely unorthodox army.
Got twice as many troops as her? Too bad, she still matches your army.
Got something nicely hidden and tucked away out of sight? Too bad, Yotanwa has these human bloodhounds on hand.
Got more archers than her? Too bad, an entire tribe’s worth of her archers can fire off five arrows at once in their opening volley.
Got a nicely defended headquarters up a vertical cliff?
Sucks to be you.
The other thing that is overlooked is Yotanwa’s organisational abilities. She took multiple armies from across an entire realm and united and organised them all into a single effective fighting force all well within her lifetime.
Yotanwa is the undisputed King of the Mountains for a reason.