Ratfolk Feats
Cheek Pouches Feat 1
Source Pathfinder Advanced Player's Guide
Your cheeks are stretchy, and you can store up to four items of light Bulk or less in these cheek pouches. None of these items can have a dimension longer than 1 foot.
As long as you have at least one item in your cheek pouches, your speech is noticeably difficult to understand.
Placing an item in your cheek pouch or retrieving one is an Interact action. You can empty your mouth with a single action, causing everything you had stored in your cheek pouches to fall to the ground in your square.
Traits
Anything that doesn't list another rarity trait (uncommon, rare, or unique) automatically has the common trait. This rarity indicates that an ability, item, or spell is available to all players who meet the prerequisites for it. A creature of this rarity is generally known and can be summoned with the appropriate summon spell.
RatfolkA creature with this trait is a member of the ratfolk ancestry.
Pack Rat Feat 1
Source Pathfinder Advanced Player's Guide
Years of packing for travel have taught you how to cram vast quantities into small spaces. You can fit an additional 50% of the listed Bulk capacity into mundane storage containers or vehicles.
For example, you can fit 6 Bulk in a backpack, or 12 Bulk in a chest. This doesn't alter the items' Bulk, nor does it change how much you can store in a magical or extradimensional storage space, such as a Bag of Holding.
Traits
Anything that doesn't list another rarity trait (uncommon, rare, or unique) automatically has the common trait. This rarity indicates that an ability, item, or spell is available to all players who meet the prerequisites for it. A creature of this rarity is generally known and can be summoned with the appropriate summon spell.
RatfolkA creature with this trait is a member of the ratfolk ancestry.
Rat Familiar Feat 1
Source Pathfinder Advanced Player's Guide
You have a pet rat that has become magically bonded to you. You gain a familiar, and this familiar must be a rat. It still gets the benefits of familiar abilities, but its base form remains a rat.
Traits
Anything that doesn't list another rarity trait (uncommon, rare, or unique) automatically has the common trait. This rarity indicates that an ability, item, or spell is available to all players who meet the prerequisites for it. A creature of this rarity is generally known and can be summoned with the appropriate summon spell.
RatfolkA creature with this trait is a member of the ratfolk ancestry.
Ratfolk Lore Feat 1
Source Pathfinder Advanced Player's Guide
Years of experience among ratfolk communities have made you nimble, and you've learned to run and hide when enemies threaten.
You gain the trained proficiency rank in Acrobatics and Stealth. If you would automatically become trained in one of those skills (from your background or class, for example), you instead become trained in a skill of your choice. You also become trained in Ratfolk Lore.
Traits
Anything that doesn't list another rarity trait (uncommon, rare, or unique) automatically has the common trait. This rarity indicates that an ability, item, or spell is available to all players who meet the prerequisites for it. A creature of this rarity is generally known and can be summoned with the appropriate summon spell.
RatfolkA creature with this trait is a member of the ratfolk ancestry.
Ratspeak Feat 1
Source Pathfinder Advanced Player's Guide
To you, the squeaking of rats and other rodents makes a strange kind of sense.
You can ask questions of, receive answers from, and use the Diplomacy skill with rodents, including beavers, mice, porcupines, rats, and squirrels, but not with other mammals, such as dogs or bats. The GM determines which animals count as rodents.
Traits
Anything that doesn't list another rarity trait (uncommon, rare, or unique) automatically has the common trait. This rarity indicates that an ability, item, or spell is available to all players who meet the prerequisites for it. A creature of this rarity is generally known and can be summoned with the appropriate summon spell.
RatfolkA creature with this trait is a member of the ratfolk ancestry.
Skull Creeper Feat 1
Source Pathfinder Lost Omens: Ancestry Guide
You wear skulls to demoralize foes. You become trained in Intimidation and gain the Intimidating Glare skill feat. If you're already trained in Intimidation, you instead become trained in a skill of your choice. If you pay 50 gp for a Splendid Skull Mask, the mask grants you a +1 item bonus to Intimidation; its usage is worn (mask).
Traits
Anything that doesn't list another rarity trait (uncommon, rare, or unique) automatically has the common trait. This rarity indicates that an ability, item, or spell is available to all players who meet the prerequisites for it. A creature of this rarity is generally known and can be summoned with the appropriate summon spell.
RatfolkA creature with this trait is a member of the ratfolk ancestry.
Tinkering Fingers Feat 1
Source Pathfinder Advanced Player's Guide
You're good with your hands and can quickly improvise a fix for broken or damaged equipment. You're trained in Crafting. If you would automatically become trained in Crafting (from your background or class, for example), you instead become trained in a skill of your choice. You can Repair an item without using a repair kit without taking the -2 circumstance penalty, improvising tools from whatever you have at hand.
Traits
Anything that doesn't list another rarity trait (uncommon, rare, or unique) automatically has the common trait. This rarity indicates that an ability, item, or spell is available to all players who meet the prerequisites for it. A creature of this rarity is generally known and can be summoned with the appropriate summon spell.
RatfolkA creature with this trait is a member of the ratfolk ancestry.
Vicious Incisors Feat 1
Source Pathfinder Advanced Player's Guide
You've let your incisors grow long enough to serve as formidable weapons. You gain a jaws unarmed attack that deals 1d6 piercing damage. Your jaws are in the brawling group and have the finesse and unarmed traits. Unlike most creatures, you can file down your teeth and regrow them later on, enabling you to select this feat at any level, and to retrain into and out of this feat.
Traits
Anything that doesn't list another rarity trait (uncommon, rare, or unique) automatically has the common trait. This rarity indicates that an ability, item, or spell is available to all players who meet the prerequisites for it. A creature of this rarity is generally known and can be summoned with the appropriate summon spell.
RatfolkA creature with this trait is a member of the ratfolk ancestry.
Warren Friend Feat 1
Source Pathfinder Lost Omens: Ancestry Guide
You're adept at making contact with other ysoki. When you arrive at a new settlement, you automatically find the nearest ratfolk enclave by spending 1 day of downtime searching, provided one exists and its members aren't actively hiding from you. Once you've made contact, you gain a +1 circumstance bonus to Gather Information and Earn Income in the settlement.
Traits
Anything that doesn't list another rarity trait (uncommon, rare, or unique) automatically has the common trait. This rarity indicates that an ability, item, or spell is available to all players who meet the prerequisites for it. A creature of this rarity is generally known and can be summoned with the appropriate summon spell.
DowntimeAn activity with this trait takes a day or more, and can be used only during downtime.
RatfolkA creature with this trait is a member of the ratfolk ancestry.
Warren Navigator Feat 1
Source Pathfinder Advanced Player's Guide
You're particularly good at solving mazes and navigating twists and turns. You gain the trained proficiency rank in Survival. If you would automatically become trained in Survival (from your background or class, for example), you become trained in another skill of your choice.
When you Sense Direction or attempt a roll against a Maze spell, you get a result one degree of success better than you rolled. You don't take a penalty to Sense Direction when you lack a compass.
Traits
Anything that doesn't list another rarity trait (uncommon, rare, or unique) automatically has the common trait. This rarity indicates that an ability, item, or spell is available to all players who meet the prerequisites for it. A creature of this rarity is generally known and can be summoned with the appropriate summon spell.
RatfolkA creature with this trait is a member of the ratfolk ancestry.
Cornered Fury Feat 5
Source Pathfinder Lost Omens: Ancestry Guide
When physically outmatched, you fight with unexpected ferocity. If a foe of a larger size than you critically hits and damages you, that foe is Flat-Footed to you for 1 round.
Traits
Anything that doesn't list another rarity trait (uncommon, rare, or unique) automatically has the common trait. This rarity indicates that an ability, item, or spell is available to all players who meet the prerequisites for it. A creature of this rarity is generally known and can be summoned with the appropriate summon spell.
RatfolkA creature with this trait is a member of the ratfolk ancestry.
Gnaw 
Feat 5
Source Pathfinder Lost Omens: Ancestry Guide
Prerequisites Vicious Incisors
With enough time and determination, you can chew through nearly anything. You deal double your jaws damage to an unattended, inanimate object.
Traits
Anything that doesn't list another rarity trait (uncommon, rare, or unique) automatically has the common trait. This rarity indicates that an ability, item, or spell is available to all players who meet the prerequisites for it. A creature of this rarity is generally known and can be summoned with the appropriate summon spell.
RatfolkA creature with this trait is a member of the ratfolk ancestry.
Lab Rat Feat 5
Source Pathfinder Advanced Player's Guide
You've spent more than your share of time in an alchemy lab. You might have been an alchemist yourself, an assistant, or perhaps even a test subject. Either way, you have been exposed to a wide variety of alchemical poisons and elixirs, leaving you with increased tolerance of their effects.
You have a +1 circumstance bonus to saves against poison and harmful effects from elixirs. If you roll a success on your saving throw against an elixir or poison, you get a critical success instead.
Traits
Anything that doesn't list another rarity trait (uncommon, rare, or unique) automatically has the common trait. This rarity indicates that an ability, item, or spell is available to all players who meet the prerequisites for it. A creature of this rarity is generally known and can be summoned with the appropriate summon spell.
RatfolkA creature with this trait is a member of the ratfolk ancestry.
Plague Sniffer Feat 5
Source Pathfinder Lost Omens: Ancestry Guide
Prerequisites longsnout rat heritage
You can sniff out the pungent tang of disease. When you detect a creature by scent, you can also detect if that creature is suffering from a disease at a non-carrier state. If the disease is particularly subtle, you might need to attempt a Perception check against the disease's DC (subject to the GM's discretion).
Traits
Anything that doesn't list another rarity trait (uncommon, rare, or unique) automatically has the common trait. This rarity indicates that an ability, item, or spell is available to all players who meet the prerequisites for it. A creature of this rarity is generally known and can be summoned with the appropriate summon spell.
RatfolkA creature with this trait is a member of the ratfolk ancestry.
Quick Stow (Ratfolk) 
Feat 5
Source Pathfinder Advanced Player's Guide
Prerequisites Cheek Pouches
Frequency once per round
You are adept at quickly moving items into your cheek pouches. You Interact to store one held item in your cheek pouches (provided it fits).
Traits
Anything that doesn't list another rarity trait (uncommon, rare, or unique) automatically has the common trait. This rarity indicates that an ability, item, or spell is available to all players who meet the prerequisites for it. A creature of this rarity is generally known and can be summoned with the appropriate summon spell.
RatfolkA creature with this trait is a member of the ratfolk ancestry.
Rat Magic Feat 5
Source Pathfinder Advanced Player's Guide
There always seems to be a little rat around to carry messages for you. You can cast Animal Messenger once per day as a primal innate spell. When you do, the animal that responds is always a rat. If there are no rats within range, the spell is lost.
Traits
Anything that doesn't list another rarity trait (uncommon, rare, or unique) automatically has the common trait. This rarity indicates that an ability, item, or spell is available to all players who meet the prerequisites for it. A creature of this rarity is generally known and can be summoned with the appropriate summon spell.
RatfolkA creature with this trait is a member of the ratfolk ancestry.
Ratfolk Roll 
Feat 5
Source Pathfinder Lost Omens: Ancestry Guide
Your ability to curl up into a tight ball comes in handy. You roll up into a ball and move up to four times your Speed in a straight line down an incline. If you reach the bottom of the incline or hit an obstacle during this first turn of movement, you stop rolling safely. Otherwise, you automatically keep rolling at this Speed during subsequent turns until you hit the bottom of the incline or an obstacle ends this movement (which can happen in the middle of your turn). You're Slowed 2 each turn after the first that you keep rolling, and if you hit an obstacle on a turn after the first, you and the obstacle both take 4d6 bludgeoning damage and you stop rolling.
Traits
Anything that doesn't list another rarity trait (uncommon, rare, or unique) automatically has the common trait. This rarity indicates that an ability, item, or spell is available to all players who meet the prerequisites for it. A creature of this rarity is generally known and can be summoned with the appropriate summon spell.
MoveAn action with this trait involves moving from one space to another.
RatfolkA creature with this trait is a member of the ratfolk ancestry.
Big Mouth Feat 9
Source Pathfinder Advanced Player's Guide
Prerequisites Cheek Pouches
Your cheek pouches are especially stretchy. Instead of storing up to four items of Light Bulk in your cheek pouches, you can store up to 1 Bulk worth of items. The maximum size of a given item is unchanged.
Traits
Anything that doesn't list another rarity trait (uncommon, rare, or unique) automatically has the common trait. This rarity indicates that an ability, item, or spell is available to all players who meet the prerequisites for it. A creature of this rarity is generally known and can be summoned with the appropriate summon spell.
RatfolkA creature with this trait is a member of the ratfolk ancestry.
Overcrowd Feat 9
Source Pathfinder Advanced Player's Guide
Your physiology is slight, and you can pack into small spaces with others of similar stature.
As long as you are Small, you can end your movement in the same square as a Small ally. Only two creatures total can share the same space when using this ability or a similar one.
Traits
Anything that doesn't list another rarity trait (uncommon, rare, or unique) automatically has the common trait. This rarity indicates that an ability, item, or spell is available to all players who meet the prerequisites for it. A creature of this rarity is generally known and can be summoned with the appropriate summon spell.
RatfolkA creature with this trait is a member of the ratfolk ancestry.
Rat Form 
Feat 9
Source Pathfinder Advanced Player's Guide
You can transform into an innocuous-looking rat to scout an area or slip through tight spaces. You gain the effects of a 1st-level Pest Form spell, except that you must assume the battle form of a Tiny rat.
Traits
Anything that doesn't list another rarity trait (uncommon, rare, or unique) automatically has the common trait. This rarity indicates that an ability, item, or spell is available to all players who meet the prerequisites for it. A creature of this rarity is generally known and can be summoned with the appropriate summon spell.
ConcentrateAn action with this trait requires a degree of mental concentration and discipline.
PolymorphThese effects transform the target into a new form. A target can't be under the effect of more than one polymorph effect at a time. If it comes under the effect of a second polymorph effect, the second polymorph effect attempts to counteract the first. If it succeeds, it takes effect, and if it fails, the spell has no effect on that target. Any Strikes specifically granted by a polymorph effect are magical. Unless otherwise stated, polymorph spells don't allow the target to take on the appearance of a specific individual creature, but rather just a generic creature of a general type or ancestry. If you take on a battle form with a polymorph spell, the special statistics can be adjusted only by circumstance bonuses, status bonuses, and penalties. Unless otherwise noted, the battle form prevents you from casting spells, speaking, and using most manipulate actions that require hands. (If there's doubt about whether you can use an action, the GM decides.) Your gear is absorbed into you; the constant abilities of your gear still function, but you can't activate any items.
PrimalThis magic comes from the primal tradition, connecting to the natural world and instinct. Anything with this trait is magical.
RatfolkA creature with this trait is a member of the ratfolk ancestry.
TransmutationEffects and magic items with this trait are associated with the transmutation school of magic, typically changing something's form.
Uncanny Cheeks Feat 9
Source Pathfinder Lost Omens: Ancestry Guide
You squirrel away useful objects and seem to retrieve them at just the right time. You gain the Prescient Consumable and Prescient Planner feats, except that you always withdraw the objects from your cheek pouches. This means the object you retrieve must fit in your cheek pouches; this is generally an item of negligible Bulk unless you also have the Cheek Pouches feat.
Traits
Anything that doesn't list another rarity trait (uncommon, rare, or unique) automatically has the common trait. This rarity indicates that an ability, item, or spell is available to all players who meet the prerequisites for it. A creature of this rarity is generally known and can be summoned with the appropriate summon spell.
RatfolkA creature with this trait is a member of the ratfolk ancestry.
Shinstabber Feat 13
Source Pathfinder Lost Omens: Ancestry Guide
Prerequisites Overcrowd
You can dart around and between your larger allies' legs without tripping them up. As long as you're Small or smaller, you can end your movement in the same square as a Medium or larger ally. Only two creatures total can share the same space when using this ability or a similar one.
Traits
Anything that doesn't list another rarity trait (uncommon, rare, or unique) automatically has the common trait. This rarity indicates that an ability, item, or spell is available to all players who meet the prerequisites for it. A creature of this rarity is generally known and can be summoned with the appropriate summon spell.
RatfolkA creature with this trait is a member of the ratfolk ancestry.
Skittering Sneak Feat 13
Source Pathfinder Lost Omens: Ancestry Guide
You squish, slink, and skitter from cover to cover with great speed and stealth. You can move up to your full Speed when you Sneak.
Traits
Anything that doesn't list another rarity trait (uncommon, rare, or unique) automatically has the common trait. This rarity indicates that an ability, item, or spell is available to all players who meet the prerequisites for it. A creature of this rarity is generally known and can be summoned with the appropriate summon spell.
RatfolkA creature with this trait is a member of the ratfolk ancestry.
Warren Digger Feat 13
Source Pathfinder Advanced Player's Guide
You've learned to put your sturdy claws to work digging through the earth. You gain a Burrow Speed of 15 feet.
Traits
Anything that doesn't list another rarity trait (uncommon, rare, or unique) automatically has the common trait. This rarity indicates that an ability, item, or spell is available to all players who meet the prerequisites for it. A creature of this rarity is generally known and can be summoned with the appropriate summon spell.
RatfolkA creature with this trait is a member of the ratfolk ancestry.
Ratfolk Growth Feat 17
Source Pathfinder Lost Omens: Ancestry Guide
You call upon the familial bonds you share with other ysoki to defend them in battle. You can cast Enlarge as a 6th-level primal innate spell once per day. You can target only yourself and other ratfolk with this spell.
Traits
Anything that doesn't list another rarity trait (uncommon, rare, or unique) automatically has the common trait. This rarity indicates that an ability, item, or spell is available to all players who meet the prerequisites for it. A creature of this rarity is generally known and can be summoned with the appropriate summon spell.
RatfolkA creature with this trait is a member of the ratfolk ancestry.