[thejeff]

Yeah, makes them useless in combat, but still good for research/rituals.

In CBM, Transformation is better, though the amulet is still cheaper and leaves you with full slots. Transformation is kind of random. Can't it kill the mage? In vanilla, the amulet is much cheaper and available much earlier.
And of course it can be used on any mages, not just N. Probably works better on expensive human mages than on Pan though. Or, as Burnsaber pointed out, those with minimal slots.
Life after death is a lot harder to set up.