Maeldrun’s Death Grip (Sor/Wiz 4)

   This spell when cast enables the caster
to conjure an insubstantial magical force directly around
a target’s neck. This force then attempts to strangle the
victim forcibly. The choking force inflicts 1d4 points of
physical damage for every 2 levels of the caster each round
the target is affected. The spell lasts its duration whether
the caster concentrates on it or not.

   If a successful fortitude save is made
the victim can still croak out a few words and it is possible
to even cast spells, although a concentration check must be
made for any verbal spells in addition to the normal concentration
check needed for the continuing damage taken by this spell.
A failed save indicates that the target can’t perform any
verbal action or concentrate on casting a spell. They also
suffer a -2 to all actions and skill checks due to the inability
to focus.

   The caster must concentrate to continue
the damage inflicted by the spell on an opponent (a standard
or move action). The target of the spell may be changed at
will by the caster as often as desired but only once per round,
until the duration of the spell ends.

   The force created by the spell ignores
armor and physical barriers since it is created precisely
at the spot needed to "choke" and vanishes out of
existence when not being used. This also means that the spell
ignores all barriers in-between the caster and the target,
but the caster must be able to see their target.