Dead Demon Consuming Seal

This seal invokes the powers of the death god (shinigami). Once called upon, the death god hovers behind the user and inserts its arm into their soul. At this stage only the user can see the death god. To perform the seal the user need only grasp the target. The death god's arm extends from their chest and grabs the soul of the target, immobilizing them and allowing them to see the death god as well. Soon after the sealing is completed the death god consumes the user's soul, sentencing them to an eternity of battle in its stomach. A swirl-pattern is left on the stomachs of those that have had something sealed within them using this jutsu.

There are many mysteries surrounding this seal, and the exact workings seem to be known to no-one. One of the mysteries is how the Fourth Hokage managed to leave behind some of his life energy to act as a fail-safe.