while any of those gathered here might be more powerful than an individual Bourbaki, our "heroes" were fighting individually at random, while the Bourbaki are a unified whole. Though Bourbaki may not outnumber their opponents for once, the more that gather the greater they become.
So lets resolve this chronologically, for convenience sake.
Yu responds to the Bourbakis' aggression with a burst of lightning. The one up front, #1, slams his staff into the ground, forming the same circle that 4 had created earlier. Instead of an attack, they form a transparent barrier to cover itself, the two adjacent to it, 2 and 3. This barrier begins to crack, but manages to protect the three.
6, three Bourbaki down to Yu's left, does the same, creating a shield to protect its neighbors, 4 and 8.
Finally, rather than raising a barrier, 5 steps out from its position behind 3 to raise his staff high, absorbing what was left of the lightning aimed at the right side. This part of Yu's lightning is drawn into 5's staff, before being directed to Chie, the one who dared to leap towards them.
Muse's beam finishes off 1's barrier, however 4 steps forward to absorb the flame aimed at the other left-side barrier, taking and harnessing the power to use for its own attack.
In this case, 4's attack is launching a blast of fire at Sumeragi, in the form of an intense wave of flame that reaches up towards the sky in an attempt to keep them well away.
As with the few before it, 7 raises its staff to absorb Chie's ice, protecting its neighbors 5 and 9 while powering up its next attack.
the ice finishes off 6's barrier, leaving 4, 6, and 8 vulnerable to future attacks this round, but those seemed to be few and far between.
Meaning that, 1, 2, and 3 are defenseless. Their robes are pierced by shards of ice, but the figures don't seem to respond in any meaningful way. As if there were nothing left of them but their devotion, they seem willing to push on despite injury.
Since 7 is already busy, it doesn't protect itself from Sana's psychic? Attack. However, 9 is under no such restrictions. As 7 had protected it from the ice, 9 protects 7 from the psychic attack, with the mist and force all being absorbed into its staff.
Finally, Kazuo aims his gears at 4. With their barrier down, the gears are able to strike through 4's robes. Though its form is battered, leaking out some form of.. Purple-ish energy, its not yet defeated, eager to join its companions in their counterattack.
And this is the fun part dear viewers. Where the Bourbaki unite their counterattack
Since Sumeragi is the closest, 2 decides to focus on them. The creature strikes the ground like 4 had last turn, charging for only a second before launching a green, energy projectile at Sumeragi. Like the blue one aimed at Kazuo earlier, it wouldn't hurt much, however Sumeragi would find their movements slowed to a crawl.
7 retaliates at Sana's attempt to strike them, forming Chie's shards into a single, massive spear aimed to impale Sana in a single strike.
9 takes after 5's target, aiming Sana's disorienting psychic blast at Chie, aiming to deal serious mental damage as well as debilitate their foe.
as one left undisturbed, 3 waves its staff in a circle to whip up a breeze before sending a small tempest at Kazuo. This tempest may pick up some of Kazuo's leftover gears while aiming a slicing breeze at him
Finally, 8 doesn't make an attack at all, keeping watch over the conflict as he continues rambling
8: Souls... Fresh souls for master...
2: More souls...
3: Fresh offerings....
Whenever one of the creatures speaks of "master" their voice becomes almost euphoric, with their movements becoming more energetic, eager to serve their only care.