Terrible Hybrid Thing

Terrible Hybrid Thing CR 10

XP 9,600
CE Large aberration (mythos)
Init +6; Senses darkvision 60 ft., see in darkness; Perception +11


AC 18, touch 11, flat-footed 16 (+2 Dex, +7 natural, –1 size)
hp 125 (10d8+80 plus 10); regeneration 100 (bludgeoning, fire, or acid)*
Fort +13; Ref +5; Will +10
Defensive Abilities caustic blood*; Immune cold, confusion and insanity effects, critical hits, hunger, sneak attacks, thirst


Speed 30 ft., fly 50 ft. (good)
Melee 2 claws +13 (1d6+6), bite +12 (1d8+6 plus grab)
Special Attacks blood drain (1d3 Constitution), bloodlust
Spell-like Abilities (CL 10th; blood point cost to cast noted with each spell):


Str 22, Dex 14, Con 26, Int 14, Wis 17, Cha 19
Base Atk +7; CMB +14 (+18 grapple); CMD 26
Feats Flyby Attack, Great Fortitude, Improved Initiative, Toughness, Weapon Focus (claw)
Skills Acrobatics +15, Fly +17, Knowledge (religion) +15, Perception +16, Stealth +11, Survival +16
Languages Aklo, Common, Necronomusll7-56
SQ blood pool (12 blood points [24 max]), low metabolism, no breath, starflight, Yellow Sign affinity


Bloodlust (Ex)

When a void-stirge successful bites a living creature, it is swiftly driven to a frenzied bloodlust. For 1 minute after it bites a target, it gains a +2 morale bonus on attack and damage rolls against that target. A void-stirge has no limit as to how many simultaneous bloodlust targets it can have at any one time, but it generally focuses on the same target once its bloodlust is engaged. It also gains these bonuses on attack and damage rolls against creatures taking bleed damage from any source.

Blood Pool (Su)

When a blood magic creature inflicts the dead condition upon a non-plant living creature, it gains 1 point in its blood pool. If it kills a creature with blood designated as special (GM adjudication) its blood pool is filled. The maximum number of blood points it can possess in its pool is equal to 10 + its HD + its Cha modifier. Any points above its blood pool’s maximum are lost. A blood magic creature can activate this template’s special abilities by expending blood points or it can be used to enhance any of the creature’s abilities. Spending a blood point is a free action that cannot be used to create the same effect or provide more than one of the benefits listed below in the same round. Spending a blood point grants the creature any of the following benefits: +2 to any one d20 roll. +2 to the DC of any extraordinary, spell, spell-like or supernatural ability. During any round in which a blood magic creature takes a full attack action, it may spend 1 blood point to make an extra attack at his highest base attack bonus. Blood points may be used in this way with both melee and ranged attacks. This does not stack with haste or the speed special weapon ability. At the beginning of a blood magic creature’s turn, it may spend 1 blood point to gain the benefit of a feat it does not have. It must meet the prerequisites of the feat. It gains the benefit until the beginning of his next turn. Spellcasters who prepare their spells in advance can spend 1 blood point to recall any spell just cast.

Caustic Blood (Ex)

If an blood magic creature is damaged by a slashing or piercing melee weapon, the wielder suffers 2d6 points of acid damage (DC 23 Reflex save for half). As an additional effect a blood magic creature can expend 1 blood point to make the blood toxic as well as acidic. It may select any one poison it is aware of. The save DC for both of these effects is Constitution-based.

Black Lotus Extract (Su)

Caustic blood—contact; save DC 23; onset 1 minute; frequency 1/round for 6 rounds; effect 1d6 Con damage; cure 2 consecutive saves.

Low Metabolism (Ex)

While a void-stirge craves blood if it has not fed within the last 24 hours, it does not suffer any negative effects from starvation, and it can, in theory, survive forever without drinking or feeding. It is immune to effects that induce magical starvation or thirst, yet it still seeks to drink blood whenever it can to sate its desire. Its strange metabolism and body also render it immune to critical hits, sneak attacks, and other forms of precision damage.

Regeneration (Su)

A blood magic creature can activate its regeneration ability (equal to 10 points per HD the blood magic creature possess [Maximum 150]); bludgeoning, fire, or acid, at a cost of 6 blood points.

Starflight (Su)

A void-stirge can survive in the void of outer space, and it flies through space at incredible speeds. Although exact travel times vary, a trip within a single solar system normally takes it 3d20 months, while trip beyond normally takes it 3d20 years (or more, at the GM’s discretion)—provided the voidstirge knows the way to its destination.

Yellow Sign Affinity (Ex)

A void-stirge is immune to the effects of the Yellow Sign, and by concentrating, it can locate the nearest active Yellow Sign as per discern location (CL 20th). When an active Yellow Sign is visible, a void-stirge gains fast healing 2 and a +4 enhancement bonus to its Dexterity. An active Yellow Sign is either one that was created by Hastur or by the yellow sign spell. Inactive Yellow Signs, such as the unholy symbols carried by cultists of Hastur, do not bolster a void-stirge, but these creatures generally treat those who openly wear such symbols as allies. A character who displays a Yellow Sign in this manner gains a +5 circumstance bonus on all Bluff, Diplomacy and Intimidate checks against a void-stirge.


These aberrations are vaguely humanoid in shape with two upper limbs and two lower limbs on a torso with a head in the usual location, but there the resemblance ends. They are not altogether crows, nor moles, nor buzzards, nor ants, nor vampire bats, nor decomposed human beings, but something both more and less, and when not flying they flop limply along, half with their webbed feet and half with their membranous wings (See “The Festival” by H.P. Lovecraft).

Terrible hybrid things are eldritch abominations that look like void-stirges of prodigious size but with a blood-red tint to their skin rather than the grayish black of their compatriots.

They are able to draw mystical power from the blood they drain to make themselves even more frightfully deadly.

The eekhayab and void-stirge are each based on different interpretations of the byakhee from the Call of Cthulhu game and the stories of H.P. Lovecraft, and that name is the property of Chaosium Inc., and is not Open Content. However, like Chaosium before us, we are basing the description of the creature on the H.P. Lovecraft short story “The Festival”, which is in the public domain. Therefore, we are adapting the existing stat block but have to change the name of the beast for use in this adventure.

Section 15: Copyright Notice

Mythos Monsters (PF1) © 2022, Legendary Games; Authors Jason Nelson, Jim Groves, Jonathan Keith, Tom Phillips, Alistair J. Rigg, and Greg A. Vaughan

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