Carl's patch stores soul power in a nearly full bar that creates an ominous neck itch and a strategic choice about when to discharge it.
The patch on Carl's back accumulates soul energy from kills. By token six its bar is almost, but not completely, full.
Carl has noticed no clear harmful effect, yet he feels an increasingly persistent itch near his neck whenever the charge approaches maximum. The sensation makes him uneasy.
He can disperse the stored power after one or two more kills, but the sparse phase-two enemy path may not refill it before the final key boss. Carl chooses to retain the charge through the saferoom reset.
A dark back patch with a nearly full soul gauge sending faint tendrils toward the wearer's neck.
The patch is a powerful reserve whose unknown side effects compete with Carl's desire to save it for the boss.