Tymessul's Improved Planar Pacifier

A 9th-level version of the base spell is rumored to exist. It does not require a hit point invested per item and its effects apply at 18th, 24th. 30th. And 36th levels, respectively.

This effect can be made permanent only by a complex process, in which the item is partially unmade and remade, with a minimal additional cost of 10,000 gp. A hit point is given up in the process, although this can be from the item's owner. Failure might destroy the item (any chance of this is decided the DM).