Sandy petersens cthulhu mythos 309

Attacking the brain cylinder is a sunder combat
maneuver and applies damage normally to the brain

from size as a result.)

cylinder itself. An attacker familiar with mi-go

Saves: A brain cylinder with class levels retains its

mechanisms can also detach the brain cylinder with

saving throw modifiers from its class levels. A brain

a grapple combat maneuver. In either case, the drone

cylinder without class levels has base saves of +0 for all

gains a +4 bonus to its CMD against such attacks

three saving throws as a result of its one racial HD as

from below or from creatures smaller than it but a –4

a construct.

penalty to its CMD against these attacks from above or
from larger creatures.

Creating a Brain Cylinder
“Brain Cylinder” is an acquired template that can be
added to any corporeal living creature that has a brain

(referred to hereafter as the base creature).
Challenge Rating: A brain cylinder has limited
methods of interacting with the environment and
typically has no way to attack or defend itself physically,
giving it a CR of 1/4. If a brain cylinder retains spell-like
abilities, psychic magic, or other significant methods of
attacking and defending itself, its CR is equal to that of
the base creature –1.
Type: The creature’s type changes to construct.
Size: The creature’s size is reduced by three size
categories (minimum size Diminutive).
Senses: A brain cylinder is blind and deaf unless it
has active attachments that grant it vision and hearing.
Typically, these attachments only grant vision and
hearing equivalent to those of a human, so it loses lowlight vision or darkvision. A brain cylinder loses all
other senses that depended upon a physical body.
AC: A brain cylinder loses all natural armor bonuses
possessed by the base creature, but gains a +6 armor
bonus from its armored glass casing.
Hit Dice: A brain cylinder drops all racial HD but
one and changes that one racial HD to a d8. Creatures
with class levels retain their HD. As a construct, a
brain cylinder does not have a Constitution score and
does not gain bonus hp from this ability, but it does

302

(Most brain cylinders are Tiny and gain no bonus hp

gain bonus hp according to its size if it’s large enough.

Defensive Abilities: A brain cylinder gains
hardness 20 from its armored glass casing. It is immune
to cold damage and takes half damage from fire and
sonic damage. Any energy damage (except electricity
damage) inflicted on a brain cylinder is halved before
applying its hardness to determine actual damage.
Ranged weapon damage is halved as well, and brain
cylinders are immune to nonlethal damage and critical
hits.
Weakness: A brain cylinder is immobile and is
treated as an object. In addition to having a Dexterity of
0 (and thus gaining a –5 penalty to AC), a brain cylinder
has an additional –2 penalty to its AC. Furthermore,
a creature can take a full-round action to line up an
attack against a brain cylinder to automatically hit
with a melee weapon or gain a +5 bonus on attack rolls
with a ranged weapon.
Speed: A brain cylinder is immobile. It loses all the
base creature’s speeds.
Attacks: A brain cylinder has no method of
attacking. It loses all the base creature’s natural attacks.
Special Attacks: A brain cylinder loses all special
attacks that rely on the base creature’s physical body.
It retains all spell-like abilities possessed by the base
creature, as well as all purely mental abilities. If the base
creature was capable of casting spells, it retains that
ability but cannot cast spells with somatic, material, or
focus components. It can only cast spells with verbal
components if it has a speech module attached (see

Languages, below), and cannot target spells if it has no
vision module attached. Without a hearing module, a