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Yllosan CR 7

A pale, translucent squid-like creature floats shrouded in rainbow-hued mist.

XP 3,200
CG Small aberration (incorporeal)
Init +5; Senses darkvision 60 ft.; Perception +14


EAC 19; KAC 20
Fort +6, Ref +6, Will +12
Defensive Abilities incorporeal, natural invisibility
Weaknesses vulnerable to sonic


Speed 30 ft., fly 30 ft. (good)
Ranged aetheric throw +15 (1d12+7 B or P)
Offensive Abilities possession, riding possession
Spell-like Abilities (CL 7th)

3/dayenervation (DC 19, negative levels last for 1 day per CL), suggestion (DC 18)
At willdancing lights, detect thoughts (DC 16), mind link (DC 16)


Str —, Dex +5, Con +2, Int +4, Wis +1, Cha +2
Skills Acrobatics +19, Bluff +14, Culture +19, Diplomacy +14, Stealth +19
Languages Celestial, Common, Elali, Ultari, Yllosan; telepathy 100 ft.
Other Abilities dream, mind-link, starflight


Aetheric Throw (Ex)

An yllosan can enfold a nearby unattended object (maximum 35 pounds) and telekinetically hurl it as a ranged attack. If the attack hits, the target and the thrown object each take 1d12+7 points of kinetic damage. The item’s composition or magical properties do not affect the damage it deals when thrown wrapped in aether. An alchemical weapon, grenade, or similar item thrown at a target using this ability requires a ranged attack; however, if the attack hits and the item is shattered on impact, the target is affected by contents of the alchemical weapon or detonation of the grenade as the aether sheath dissolves upon impact.

Dream (Su)

Once per day the yllosan, or a messenger it touches, sends a message to others in the form of a dream. It must first name the recipient or identify him or her by some title that leaves no doubt as to identity. The messenger then enters a trance, appears in the intended recipient’s dream, and delivers the message.

The message can be of any length, and the recipient remembers it perfectly upon waking.

The communication is one-way. The recipient cannot ask questions or offer information, nor can the messenger gain any information by observing the dreams of the recipient.

Once the message is delivered, the messenger’s mind returns instantly to its body. The duration is the time required for the messenger to enter the recipient’s dream and deliver the message.

If the recipient is awake when the spell begins, the messenger can choose to wake up (ending the effect) or remain in the trance. The messenger can remain in the trance until the recipient goes to sleep, then enter the recipient’s dream and deliver the message as normal. A messenger that is disturbed during the trance comes awake, ending the spell.

Creatures who don’t sleep or don’t dream cannot be contacted by this ability.

The messenger is unaware of its own surroundings or of the activities around it while in the trance. It is defenseless both physically and mentally (always failing any saving throw) while in the trance.

Possession (Su)

Once per day the yllosan attempts to possess a creature by projecting its soul into the target’s body. The target creature must be within 150 ft. and the yllosan must know where it is, though it does not need Line_of_Sight”>line of sight or Line_of_Effect”>line of effect to it. The target creature is allowed a DC 17 Will save. When the yllosan transfers its soul upon casting, its body vanishes.

It is ejected to the closest empty square upon expiration of the spell or upon the host’s death. Failure to take over a host ends the spell.

If successful, the yllosan’s life force occupies the host body. The host’s soul is imprisoned with the yllosan but can still use its own senses (though it can’t assert any influence or use even purely mental abilities). The yllosan can communicate telepathically with the host as if they share a common language, but only with the yllosan’s consent. The yllosan keeps its Intelligence, Wisdom, Charisma, attack bonus, save bonuses, alignment, and mental abilities. The body retains its Strength, Dexterity, Constitution, hit points, natural abilities, and automatic abilities. A body with extra limbs doesn’t allow the yllosan to make more attacks (or more advantageous two-weapon attacks) than normal. The yllosan cannot activate the body’s extraordinary or supernatural abilities, nor can it cast any of its spells or use spell-like abilities.

As a standard action, an yllosan can shift freely out of the host. If the host’s body is killed, you return to your own body and the life force of the host departs (it is dead). It is possible for the yllosan to use this ability to possess a new target from within another creature’s body; this resets the duration. Creatures whose souls are their bodies, such as incorporeal undead and non-native outsiders, cannot be possessed by an yllosan.

Riding Possession (Su)

Three times per day the yllosan can stealthily project its soul into a host’s body up to 150 ft. away as an observer, with limited ability to influence the target. This functions as the yllosan’s possession ability, except the host is still in full control of its body and is unaware the yllosan is possessing it. It cannot communicate with the host directly but can cast mind-affecting spells or riding possession on the host as long as it can cast these spells as purely mental actions.

Even if the spell cast would normally affect more than one target or an area, it can affect only the host. If the host succeeds at a saving throw against a spell cast in this way, it immediately becomes aware that it is possessed, and if it was already aware, it receives another saving throw against riding possession. Protection from evil and similar effects don’t expel the yllosan from the host, but they do prevent you it from casting further spells from within the host until their durations expire. A potential host can avoid these effects by making a DC 17 Will save.

Telekinetic Invisibility (Ex)

An yllosan’s body bends light and weaves aether while dampening sound waves. This works as invisibility except that the aetheric bending is easier to notice than normal invisibility, so its bonus on Stealth checks is halved (+10 while moving and +20 while perfectly still). The dampened sound allows it to avoid automatic detection via sound-based blindsense and blindsight, but it does not gain any bonus on Stealth checks from this ability against a creature with such abilities. This is considered a natural invisibility effect and is thus not subject to magical effects that would end an invisibility spell.

Vulnerable to Sonic (Ex)

An yllosan suffers an additional 50% damage from sonic energy attacks. In addition, if caught within a sustained sonic effect which deals 5 or more points of damage per round, it cannot attack and can take only a single move or standard action. An yllosan that is possessing a creature using greater possession or riding possession is not harmed by sonic effects, but if it is struck by a sonic effect that deals 15 or more points of damage while possessing a creature, the yllosan is driven out of its host automatically and staggered for 2d4 rounds.


Environment any
Organization solitary, pair, or cluster (3–6)

A powerful telepathic and telekinetic species, the yllosan (ee-LOE-san) are mysterious ghostlike beings that exist in a realm of pure thought, floating intangible through the material world of others. They communicate by telepathy and revel in infiltration of other societies, extending their incorporeal tentacles into the mind and heart of creatures they meet to walk among them and search for those of good heart to offer advice or warning about evils in their midst or coming soon.

An yllosan may step into the body of a creature to help it achieve a goal or task it fears to attempt on its own. Yllosan are emissaries of hope and inspiration, but rarely stay too long in one place or within one body. They see themselves as advisors and helpers; it is not their place to do too much for those they meet, but to motivate them to rise up and face new challenges, daring to find the greatness within themselves. Yllosan rarely reveal their true form to other races, preferring to work through possessed proxies while remaining in the shadows themselves.

Yllosan have long cultivated a reputation among the enemies of the Accord as master spies and tireless investigators, and they enjoy the paranoia they engender in their foes. They are not above simply playing pranks on enemies while walking secretly among them, moving small objects around and using its suggestion and possession abilities to cause enemies to perform incriminating acts that cause their erstwhile allies to turn on them. Their presence is difficult to detect, as they can erase the memories of creatures they have inhabited upon departing their minds.

Yllosan are 3 feet in length, though their dangling tendrils and the misty psychic shroud that surrounds them sometimes makes them appear larger. As creatures of pure thought, they are weightless and virtually impossible to detect while possessing another creature; however, they are visible to creatures able to see invisible when entering or departing a possessed target.

Section 15: Copyright Notice

Alien Bestiary (Starfinder) © 2018, Legendary Games; Lead Designer: Jason Nelson. Authors: Anthony Adam, Kate Baker, John Bennet, Eytan Bernstein, Robert Brookes, Russ Brown, Duan Byrd, Jeff Dahl, Robyn Fields, Joel Flank, Matt Goodall, Robert J. Grady, Jim Groves, Steven T. Helt, Thurston Hillman, Tim Hitchcock, Nick Hite, Daniel Hunt, Mike Kimmel Marshall, Isabelle Lee, Jeff Lee, Lyz Liddell, Jason Nelson, Richard Pett, Tom Phillips, Alistair J. Rigg, Alex Riggs, Wendall Roy, Mike Shel, Neil Spicer, Todd Stewart, Russ Taylor, Rachel Ventura, Mike Welham, George Loki Williams, Scott Young.