While surveying the stone warehouse in the Land of Rivers, Gen rearranged the diagram of the four restriction layers.
Every previous plan had started with "how to extract the core."
But Black Zetsu's core was bound to the heart. Extracting it directly would inevitably trigger the innermost layer.
The proper sequence had to be reversed.
First, strip the core of its ability to issue commands externally.
Then stabilize the white tissue it controlled.
Only then could Obito himself sever the authorization line connected to his heart's chakra.
Gen proposed a three-stage procedure.
Stage one: disrupt synchronization.
The Sealing Squad would use the two Black Samples to create three false heartbeat sources.
When Black Zetsu triggered the core remotely, he would receive four nearly identical core responses at once, leaving him unable to determine which belonged to Obito.
They first tested that assessment in an isolation box.
The Sealing Squad placed an active Black Sample before one genuine remnant and three imitation heartbeat sources.
When only the genuine remnant was present, the sample immediately coiled around its target.
After all four were activated together, it chose incorrectly three times in a row before reaching the genuine remnant on its fourth attempt.
Those mistakes were enough to buy twenty to thirty heartbeats.
Gen did not write that up as a guarantee of success.
Black Zetsu had already seen one test and might identify the deception faster in an actual operation.
The first stage, therefore, was only meant to create an opening at the start. They could never rely on it to sustain the entire treatment.
It could not keep Black Zetsu trapped for long.
But it could briefly interrupt the ongoing backlash.
Stage two: stabilize the outer layer.
The Medical Squad would wrap inactive white tissue around the three restriction nodes to