Se você quiser seguir o livro de regras, eles podem criar um portal logo abaixo de Abhoth, levando essa abominação a outro tempo / mundo / dimensão
Gate Spells
The idea of a panel that would open on some remote world
impressed Eibon as being rather fantastic, not to say farfetched.
— Clark Ashton Smith , The Door to Saturn.
Cost: variable POW see Table XIII: Gate Creation and Travel Costs Cost to
access a Gate: variable magic points and 1 Sanity point
Casting time: one hour per POW spent Gate spells allow the caster to
create doorways between other lands or times, dimensions, or
worlds—allowing the user to travel great distances with a
simple step. Usually a Gate connects to a single other location.
Creation of a Gate requires the permanent expenditure of POW, in a sacrifice equal to the log to base 10 of the distance the
Gate connects in miles times five. A Gate may take many forms,
common ones being indicated by a pattern of painted lines on
a floor or a peculiar arrangement of stones in a field. Using the
Gate costs a number of magic points equal to one-fifth of the POW
originally used to make the Gate. Each trip through a Gate costs 1
Sanity point. Should the user lack enough magic points for a trip,
the traveler expends hit points to make up the cost. Return trips
through a Gate always cost the same as the initial journey.
Ordinarily, anyone or anything can move through a Gate, though some have been built so that a certain key—a word or
gesture—is needed to activate the portal. Certain versions of
the spell are known that also ‘change’ those who pass through, to aid
survival on an alien world. There are also hints that some Gates are
capable of more than one destination.
Mas você pode criar o feitiço que quiser, você sabe. O livro de regras convida você a fazer isso! :
Spell Variations
There is no such thing as a definitive spell. The
ones listed here are only a guide and starting point for the
Keeper to draw upon.
(...)
Altering a Spell
Try to insert some personal touches to the
spell, tying it more strongly to your scenario,
investigators, and story, if possible. Location: consider the
locations in your story; could one of them be linked to
the spell? If the investigators are dealing with ghouls, for
example, a spell that must be cast underground suddenly takes
on an added dimension. Spell components: the specific items
required to cast the spell. Could it be that the investigators
need the curved silver dagger they saw in the previous session at the
British Museum? Spell ritual: a greater spell effect usually
means a more complex and involved ritual. Consider where,
when, and how the spell is cast. Do the investigators have
to daub themselves in blood at the full moon and inscribe
a ritual circle? Spell description: this can range from subtle to
dramatic. Try to imbue the description with strange smells,
disorient- ing visions, curious sounds, and disturbing sensations—re-
member that most of these spells erode the caster’s sanity,
and the way in which you describe the casting should make this
manifest