Add Cigotuvi's Embrace

Grab all nearby corpses and turn them into armour + sh. (SH for
consistency with the bone plates mutation, and also to make it a
little more distinctive.)

1/3 of a point of SH & AC per skeleton, 2/3rds per corpse,
minimum one point if you hoovered any corpses/skeletons at all.
casting. Multiple casts stack. Taking damage or blocking hits has
a chance of causing you to lose 1 point; chance decreases with
spellpower. Incompatible with Stoneskin/Ozo's. Does not decay
over time, ironically.

Intent is to replace Twisted Resurrection, which has been
considered a Problem Spell for some time, with another & more
novel use for corpses.
Replace Twisted Resurrection with Cigotuvi's Embrace

As a player spell.

Twisted Resurrection has been considered a 'problem spell' for
some time: it's highly redundant with other minion-creating
necromantic spells (animate skeleton/dead, simulac), and the ways
in which it's distinct from them are not good. Cigotuvi's should,
hopefully, be a more interesting alternative use of corpses...
Add monster Cigotuvi's Embrace (Hangedman)

To hellwings, which start with it active.

+(6 + hd/3) AC & SH (single-leve); for hellwings, that's +8 of
each. 1/4 chance of falling off every time they're hit or block.