The white handprint had not appeared in the photographs taken at the scene back then.
The ruins of Kannabi Bridge had weathered many times over. Konoha could not simply return to the site and collect samples.
But the Supplyman had brought back a pair of muddy work boots that year.
Suspecting that the mud might contain enemy explosive powder, the logistics team had scraped off a small bag of samples and sealed it away.
The samples were later found to contain no explosive components. They had been classified as ordinary war-zone soil and had not been destroyed.
It took the Anbu half a day to find that cloth bag in an old warehouse.
The seal was intact.
Its number matched the Supplyman's mission checklist.
The soil had dried into hard clumps, but a few gray-white fibers, almost invisible to the naked eye, were embedded in the surface.
The Medical Squad first divided the sample into three portions.
One was compared with tissue shed by the living White Zetsu.
One was compared with the support structures in the Underground Mine Tunnel.
The last was left untouched to prevent the analysis from consuming the entire old sample.
To rule out warehouse contamination, the Medical Squad also retrieved six bags of ordinary soil samples sealed during the same period and stored on the same shelf.
All six samples had picked up cloth fibers, wood shavings, and adhesive from the seals, but none contained gray-white, web-like cells.
The person responsible for opening the bags also changed gloves three times, and a recording ninja documented the sequence of every operation.
Under chakra illumination, the black, hardened fragment revealed a dense pattern of tiny pores.
It was not charcoal.
It looked more like a hard shell formed when some kind of plant skin was exposed to