Aboleths take a different approach to equipment than most other sapient creatures; rather than working with non-living materials, they prefer to shape living things to their purpose. This doesn't mean that they don't create equipment, just that aboleth-created gear is noticeably alive. These devices have heartbeats, living organs, and body heat.

Adventurers with the sunless mariner background can buy aboleth equipment during character creation.

Gill Symbiote. This bizarre, collar-like mask fits like a sleeve over the user's lower face and neck. It extends tendrils down the user's throat when donned, a process that requires the wearer to make a DC 11 Wisdom save to avoid gaining a level of strife . Once in place, the symbiote allows the user to breathe air and water, but it also distorts the wearer's voice. Whenever the wearer speaks, other creatures must make a DC 10 Intelligence check to understand what they are saying. In addition, a creature wearing a gill symbiote must make a DC 10 Intelligence check to cast a spell with vocalized components. On a failure, the creature expends the spell slot to no effect.

Octopack. This bulbous, fleshy mass attaches itself to the wearer's back and can sprout four tentacles on demand. The tentacles aren't able to hold items, but they grant advantage on checks to maintain a grapple and grant an expertise die on Athletics checks related to climbing.

Parasite Launcher. This bracer-shaped creature has ray-like skin and several rows of glowing, fluid-filled membranes on its "back," which typically sits atop the user's forearm. Swimming in the fluid are tiny, snake-like creatures with nasty, tooth-filled maws. The launcher is a ranged weapon with a range of 30/60. It is fired via mental commands rather than a physical trigger. On a hit, the parasite deals 1d4 piercing damage. A creature hit by the parasite launcher can use its reaction to make a DC 13 Dexterity saving throw . On a success, the target tears off the parasite before it gains purchase. If the creature does not remove the parasite, the parasite begins burrowing into the target's flesh, dealing 1d4 piercing and 1d4 psychic damage at the start of each of the target's turns. A creature can use action to cut out the parasite, dealing 2d6 slashing damage to the target but ending the piercing and psychic damage. Unless removed, the parasite continues to burrow for a number of rounds equal to the proficiency bonus of the creature that fired the launcher. The parasite then dies inside the target, and the target suffers a level of strife from the trauma of the experience. The parasite launcher does not cover the user's hand, leaving it free to wield other devices or weapons. A parasite launcher can be fired from an arm that is wielding a weapon, but not a shield. The launcher holds eight parasites, and the "ammunition" regrows after 24 hours.

Sleepless Mask. This disturbing, fleshy mask covers the upper half of the wearer's face and features three, vertically placed eyes in the manner of an aboleth . While the mask is worn, each eye takes an 9-hour turn sleeping while the others remain awake, effectively sleeping for the wearer and allowing them to stay awake indefinitely. The wearer must still sleep or meditate to receive the benefits of a long rest . In addition, the tendrils that the mask sends into its wearer's brain subtly influence them toward obedience to aboleths. The wearer suffers a -1d4 penalty on saving throws against aboleth abilities and the Sea Change disease.

Air Bladder. An air bladder is similar to a water-skin but can hold up to 2 gallons of air when fully inflated, allowing for four breaths. It has a valve at the opening, eliminating the need for removing and replacing a cover or cap. When at least half inflated, an air bladder can also function as a flotation device, granting a creature holding it advantage on Athletics checks to avoid sinking.

Alchemical Weapon Oils. These oils can be applied to a weapon, increasing the damage the weapon deals and sometimes providing other benefits. Applying an alchemical weapon oil requires an action, and the effect lasts for 1 hour.

• Corrosive Oil. A weapon coated with this pungent green liquid deals an additional 2d6 acid damage.
• Frigid Oil. A weapon smeared with this bluish-white paste deals an additional 1d6 cold damage.
• Glaring Oil. Sometimes called "portable sunlight," this cloudy, silvery-white oil sheds bright light in a 20-foot radius and dim light for an additional 20 feet. A weapon treated with glaring oil deals an additional 2d6 radiant damage.
• Lifebane Oil. This viscous black liquid trails thing, mist-like tendrils of darkness at all times. A weapon coated with lifebane oil deals an additional 1d8 necrotic damage.
• Scorching Oil. This thin red oil ignites when exposed to air. A weapon coated with scorching oil deals an additional 1d6 fire damage and sheds bright light in a 10-foot radius and dim light for an additional 20 feet.
• Shocking Oil. This vibrant yellow oil arcs with a powerful electrical current. A weapon coated with shocking oil deals an additional 1d4 lightning damage and sheds dim light in a 20-foot radius.

Ascender/Descender. These small metal devices allow better control of ropes when climbing up (ascender) or sliding down (descender), granting a creature using them an expertise die on Athletics checks to move in the corresponding direction. Despite their similar names, ascenders and descenders work differently. Ascenders are mechanical devices that assist in climbing. Descenders are small metal loops that facilitate better control of ropes while rappelling. A creature can use only one of these devices at a time. The listed price is for a set of one of each device.

Boat, Collapsible. When deployed, this two-person boat resembles a kayak or canoe. It can hold up to 500 pounds without sinking and can fold up enough to be carried by a single humanoid. (While folded, the boat has the Bulky property; a creature can carry a number of bulky items equal to one plus its Strength modifier.) Setting up the boat (which comes with two folding paddles) or collapsing and packing it takes 20 minutes.

Cave Tent. This tent has a padded base and anchor points at the peak. It dampens sound and minimizes the vibrations produced by its occupants, which many underground predators use to hunt. Creatures sleeping or performing light activities inside the tent are invisible to tremorsense. However, a cave tent can keep out rain for only one hour before it starts to leak.

Luminescent Compass. The needled and directional markings of this compass are treated with a luminescent compound. It can be read easily in dim light or darkness .

Pole (10-foot), Collapsible. This lightweight but sturdy metal pole can telescope to a length of 10 feet but can also be locked at 3, 5, and 7 feet if desired. At its 5- and 7-foot lengths, it functions as a quarterstaff. At its 3-foot length, it functions as a club.

Rope Ladder. This collapsible ladder is made from two ropes connected to a series fo rungs, with a pair of hooks at the top to anchor it. Rope ladders are easier to climb while carrying a lot of gear and can be used by creatures who lack the strength or coordination to scale a rope. A rope ladder must hang from a solid anchor point to be useful.

Basic Rope Ladder. This rope ladder has hempen ropes and wooden rungs. It is 10 feet long when deployed and can support up to 500 pounds of weight without breaking.

Heavy-Duty Rope Ladder. This model has silk rope and metal rungs. It is 25 feet long and can support up to 750 pounds, but thanks to the lighter materials it weights as much as the 10-foot model.

Snorkel. This sturdy, angled tube allows a creature swimming beneath the surface of a body of water to breathe, provided the snorkel can poke above the water level. Snorkels are invaluable for cave swimming, where there may be pockets of air but the ceiling is too close to the water for a swimmer to position their head above the surface.

Spore Netting. Base on mosquito netting, spore netting is made from giant spider silk, allowing for an even finer weave. It can keep out toxic fungus spores as well as biting insects.

Spring Holster. This bracer-like device allows a creature to draw a very small weapon such as a dagger, shuriken, or derringer from a concealed position up the creature's sleeve. Drawing a weapon from a spring holster requires a reaction but can be done at any time.

Underwater Lantern. This sturdy metal lantern uses bioluminescent fungus in a sealable glass box to shed bright light in a 5-foot radius and dim light for an additional 10 feet. As long as the fungus is tended once every 7 days, it remains useful indefinitely.

Underwater Lantern, Alchemical. Using the same compounds as alchemical torches, this lantern can burn for 1 hour, shedding bright light in a 10-foot radius and dim light for an additional 20 feet. It can be refueled for 25 gp.

Wand Bracer. This leather bracer has several channels (the usual number is five) along the underside. Each channel is sized to hold a wand or similarly shaped item, such as a throwing dagger or an individual lockpick. Once on your turn, you can draw an item stored in the bracer without using an action or interacting with the object. Stowing an item in the bracer requires an action.

Doppelganger Traits

Characters with the doppelganger heritage share the following traits:

Age. Doppelgangers age much as humans do, typically living a century or less. Their apparent age is a matter of choice.

Size. In their true form, doppelgangers can stand anywhere from 3 to 6 feet tall, but they can adopt the size and build of any Small or Medium humanoid. Your true size is Small or Medium.

Speed. Your Speed is 30 feet.

Darkvision. You can see in dim light within 60 feet of you as if it were bright light , and in darkness as if it were dim light. You can’t discern color in darkness, only shades of gray.

Shapeshifter. As an action, you can change your form and your voice to that of any Small or Medium humanoid creature you have seen before, or back into your true form. Your clothing and equipment are not transformed. You revert to your true form if you die.

Doppelganger Gifts

Doppelgangers are keen observers, with eyes that are able to see through darkness and sometimes into the minds of others. In addition to the traits found in your doppelganger heritage, select one of the following gifts.

Mindsight

Your deceptions and manipulations are aided by your eerie ability to understand what people are thinking. You gain an expertise die on Deception and Insight checks.

Telepathy

You can speak telepathically to any creature within 30 feet of you that you can see. The creature understands you only if the two of you share a language. You can speak telepathically in this way to one creature at a time.

Doppelganger Paragon

When you reach 10th level, you are an exemplar of doppelganger-kind, and you gain the following paragon gift.

Read Thoughts

As an action, you can magically read the surface thoughts of one creature within 60 feet that you can see. Additionally, until the end of your next turn, you have advantage on attack rolls and Deception, Insight, Intimidation, and Persuasion checks against the creature. You can use this trait a number of times equal to your proficiency bonus. You regain any expended uses when you finish a long rest .

Doppelganger Culture

Doppelgangers are widely distrusted. The existence of a creature with the ability to take another’s form, and perhaps even read minds, is a horror to anyone with even the most innocuous of secrets. Doppelgangers are targets of intense paranoia and are banned from many communities; when they are discovered, they are often imprisoned or executed on the spot.

Most doppelgangers live in hiding and have had to rely on their parents and immediate family to teach them who they are. Others come to terms with their powers without any help at all. There has never been a doppelganger census. Still, some manage to find each other, and many cities unknowingly host a loose society of doppelgangers who gather in secret for protection and support.

Doppelgangers know as little about their origins as they do their numbers. However, rumors tell of a place far underground where doppelgangers walk freely in their true forms. Many doppelgangers venture into caves and dungeons in search of this mythical land.

Suggested Cultures. While you can choose any culture for your doppelganger character, the following cultures are linked closely with this heritage: cosmopolitan, faceless, itinerant, kithbáin halfling, Underlander.