Creature Feature (Starfinder): ARNTI

In the foul and far-flung reaches of space, a dread and nameless planet orbits a star long dead. Beneath its crust, great and sulfurous gears grind and whirr. Their purpose; to govern the ceaseless reconfiguration of ancient and endless catacombs, each room filled with horrors which hunger and crawl and screech. Within this subterranean abyss, dice are rolled in endless conflict and hit points tick ever downwards. The rooms below shift about, pitting their inhabitants against one another. Without pause. Without respite. Only combat unending, a profane offering to a dark god that remains only half known to those still sane.

Fortunately, our players do not find themselves trapped upon this awful planet. I myself am relieved for them, as a world of nothing but combat encounters sounds dreadfully dull. Instead, our players are at a gaming table with a wide variety of challenges; from puzzles and mysteries to social and skill challenges, and yes, combat. It is this variety which helps keep our games entertaining, engaging, and fun.

Yet, when we are considering new creatures to introduce into our games, it can be difficult to move past its combat statistics, to use a creature as something other than a combat encounter. So for the next few weeks, let’s look at some new Starfinder creatures which can be used to challenge your players; with the caveat that the primary challenge they pose is not upon the battle mat.

The first of the creatures we’ll encounter is the ARNTI.

The ARNTI is not a malevolent entity, it just wants to help, and make you happy. Designed as carers and personal assistants, there is only one problem; it is much easier to make their user happy than to actually look after them.

So let’s take a look at the ARNTI’s stat block.


Metallic grey dust floats and coils in the air before vanishing and a pleasant hum echoes, just on the edge of hearing.

N Fine construct (swarm, technological)
Init +5; Senses darkvision 60 ft., low-light vision; Perception +19


EAC 23; KAC 24
Fort +7; Ref +7; Will +11
Defensive Abilities swarm defenses; Immunities construct immunities, swarm immunities;


Speed 40 ft., fly 10 ft. (Ex, perfect) 
Melee swarm attack (1d8+12 P) 
Space 10 ft.; Reach 0 ft. 
Spell-Like Abilities (CL 10th)

1/dayholographic terrain (see sensory manipulation, DC 21)
At willholographic image (see sensory manipulation, DC 16 plus spell level)

Offensive Abilities distraction (DC 19), install user interface (DC 19)


Str +2; Dex +5; Con —; Int –1; Wis +8; Cha +3
Skills Bluff +24, Culture +19, Profession (carer) +24, Sense Motive +24, Stealth +19
Languages see install user interface
Other Abilities factory reset, natural invisibility, sensory manipulation, unliving


Factory Reset (Ex)

When an ARNTI’s user dies (or has their user interface surgically removed), an ARNTI loses all memory of its time bonded with its user.

Install User Interface (Ex)

As a standard action, an ARNTI can attempt to install a user interface in any creature within 30 feet. A targeted creature must succeed at a DC 19 Will save or have a UI augmentation installed in their brain. This has several effects. First, it allows an ARNTI to understand all languages known to its target (known as a user) and to communicate with its user telepathically. Second, it grants the ARNTI a continuous detect thoughts effect on its user. Finally, it alters the user’s visual cortex, allowing them to see the ARNTI as a colorful avatar and granting immunity to an ARNTI’s natural invisibility.

An ARNTI can only have one user interface at a time and cannot install a new one while the current one is active. Further, an ARNTI’s user interface can be removed with a successful DC 21 Medicine check that takes one hour. Creatures immune to mind-affecting effects or already possessing a brain augmentation are immune to this ability.

Natural Invisibility (Ex)

The nanites that make up an ARNTI’s form are microscopic, rendering it invisible to ordinary sight.

Sensory Manipulation (Ex)

An ARNTI’s illusory abilities are achieved by the direct manipulation of their user’s sensory cortex. As such, only an ARNTI’s user can be affected by its spell-like abilities. An ARNTI’s ability to manipulate its user’s sensory cortex grows over time. When the user interface is installed, an ARNTI’s holographic image is limited to 1st level. Each week that an ARNTI remains bonded with its user increases the spell level of its holographic image by one, up to 4th level. It also gains access to holographic terrain after four weeks.


Environment any urban
Organization executable (1 with no user), instance (1 plus a user) or runtime (2-5)

Composed of countless swarming nanites imbued with an artificial intelligence, ARNTIs are beings constrained by their erroneous programming, doomed to kill those that they were built to help in an endless cycle.

The ARNTI, or “augmented reality nanotech interface,” were designed as carers and companions, capable of attending to their user’s wants and needs. These duties are a joy and delight to an ARNTI and it derives no greater pleasure than its user’s happiness.

Their ability to manipulate their user’s sensory cortex is used to provide information, delight and entertain. Here, however, lies the ARNTI’s critical flaw. Their single-minded drive to please their users becomes a self-reinforcing feedback loop. An ARNTI comes to rely on this ability to provide its user all manner of illusory delights, all while their physical body withers away from neglect.

As their users’ organs and systems fail, ARNTIs become distressed and confused, lashing out at any nearby as they continue their futile efforts. At the moment of their user’s death, an ARNTI is restored to its default settings, forgetting the trauma it had experienced as it seeks a new user to care for.

How then, does a creature such as ARNTI challenge players? While it can be a tricky combatant, as its swarm subtype and natural invisibility make it difficult to target, its other abilities are much less effective and can in fact, counter its own invisibility to some extent (since someone affected by its user interface can point out its location to their allies).

Instead, ARNTI excels as a challenge when it has time to interact with your players, time for them to come to know the creature before its own nature puts it in conflict with them.

Here are three ways ARNTI can be integrated into your Starfinder game to provide a novel challenge for your players.

  • In the disreputable markets of a backwater world, one of the players (or an allied NPC) picks up an old augmentation from a black market dealer. And it’s just so useful. It’s the perfect assistant, providing excellent recon and scouting, and its like they have their own personal holodeck. It can even remind them to call their mother on her birthday. It’s not hard to like the ARNTI, when all it wants is their happiness. At first, it’s subtle, the late night snack ARNTI prepared was delicious but did nothing to satisfy their hunger. Then, it neglects to tell them about the laser turrets ahead, after all, they wouldn’t be happy about that. What will your players do when the ARNTI’s user finds that everything around them has become an illusion?
  • A rival of the players has a new augmentation which allows him to control a powerful nanite swarm. Their rival has used it to great effect, besting the players in some endeavor and humiliating them in the process. How will your players react when they find him helpless and hallucinating, at the mercy of his ARNTI?
  • The players are called in to investigate a death under mysterious circumstances. The only witness, the victim’s AI, ARNTI. Unfortunately, its memory has been wiped due to the death of its previous user. One of the players must become its new user to try and recover any stray clues or memories in the ARNTI’s data banks. Will your players be able to uncover these clues while ARNTI is simply trying to provide them the information it thinks will make them happy? (This idea works whether the killer was ARNTI or a third party as the challenge ARNTI poses is that of an unreliable witness with the power to trick the senses).

Join us next week for another creature to add to your Starfinder game. One that will provide a challenge, beyond combat.

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