Shakugan no Shana Vol 5 pg 158

With anger and regret, with vexation, but still without holding anything back, Merihim swung
the ‘Rainbow Flame Sword’.
Just then, in the midst of that motion, he caught it.
The power rising within the girl. Not even controlled enough to form an Unrestricted Method,
an incredibly crude, untuned, simply a gathering of all her power—that was all.
Before he could understand what it meant, before he could think, the girl had acted.
Completely clumsily, she had made the gathered power explode from a single point.
‘The sole of her foot!?’
By the time he knew, the girl, now a super-speed bullet, had thrust Nietono no Shana deep
into the center of his breastplate. And again, a crude, all-out concentration of power traveled
down the blade of the ōdachi, and then,
it exploded.
The ‘Rainbow Flame Sword’, deflected in a completely wrong direction, dissolved into seven
colors in mid-air, scattered, and vanished.