Undead Conduit

By strengthening the bonding of negative energy
between yourself and an undead creature you
control, you may project your necromantic castings
greater distances than normal. For the duration of
the spell, you may cast any necromantic spell you
know and have prepared from a controlled undead
creature rather than yourself. In terms of range,
touch attacks, and area of effect, the undead creature
effectively becomes the caster of these spells, though
all other variables of the spell, such a spellcasting
ability, are yours.