Kobolds have advantage on an attack roll against a creature if at least one of the Kobolds' allies is within 5 feet of the creature and the ally isn't incapacitated. Only one Kobold in the Scatter! form can benefit from this feature per turn. 

When determining your character’s ability scores, you increase one of those scores by 2 and increase a different score by 1, or you increase three different scores by 1.

Your strength score is 8, and cannot be higher except through magical means. 

Kobolds reach adulthood at age 6 and can live up to 120 years but rarely do so. Due to your ability to replace fallen Kobolds, Three Kobolds in a Trench Coat can live indefinitely as long as all three kobolds never die.

You are chaotic. 

You are medium when unified. 

Your walking speed in your unified form is 25 feet. When scattered, each kobold has a walking speed of 30 feet. 

In your united form, three kobolds are treated as one creature. You share stats, hit points, temporary hit points, spell slots, feats, and features as if you were one creature. Any spell or condition, beneficial or harmful, that affects one of you affects all of you should you take your scattered form. Damage is taken from the shared pool of hit points.

Accustomed to life underground, you have superior vision in dark and dim conditions. 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. Additionally, you have proficiency in the Perception and Stealth skills. 

You have 3 sets of hands that can dart out of your coat at any time. You have advantage on sleight of hand checks made to steal. 

Kobolds live everywhere. You can always replace a fallen member after a long rest. Your party members, patrons, captors, landlords, or others in the vicinity are under no obligation to understand where the new kobold came from, how it found you, or how it got to whatever far-flung dimension or plane where you were resting.

Since your three kobolds are constantly balancing on each other all the time, when you are struck by a critical hit or fail a Strength or Dexterity saving throw, you must make a DC 10 Acrobatics or Athletics (your choice) check to ensure that you stay together. If you fail this check, you fall to the ground Prone, and are forced into the Scatter! feature.

It is difficult enough to find armor that would fit a Kobold. It's even harder to find armor that would fit three Kobolds.

You are only capable of donning light armor. If specifically modified, your light armor can be made to fit both your unified form and break down into your individual scattered pieces. 

As a bonus action, all three kobolds exit the trench coat and run in opposite directions. The following properties apply:

Each Kobold is one creature. 

Each Kobold maintains any attributes, conditions, immunities, proficiencies, abilities, spells etc. that the unified form has.

Each Kobold is Small and can has a movement speed of 30 feet.

Each Kobold gains the Sunlight Sensitivity feature, normally waived while inside their protective Trench Coat. If one of the Kobolds keeps the Trench Coat on, they do not gain the Sunlight Sensitivity feature, but their movement speed is halved.

Your Kobolds all share the same Initiative, and you may choose in which order you wish to act each round.

Each Kobold takes one third of the unified HP and temporary HP. Remainders may be distributed as you wish.

Once per turn abilities can only be used once per round between the three Kobolds.

You maintain the same number of attacks per Attack Action as you have in your unified form.

Only one Kobold may cast spells in any one round.

Only one Kobold may use a bonus action in any one round.

Only one Kobold may benefit from pack tactics in any one round.

Once per turn abilities can only be used once per round between the three Kobolds.

Each Kobold may take any number of items from your inventory when it emerges. If a Kobold takes an attuned item it counts and being attuned to that item, and if the Three Kobolds in a Trench Coat is reformed, the unified form regains attunement to the item.

At the cost of their movement, the Kobolds can reform into the unified form if they are adjacent to each other. Their HP is once again pooled together, and any conditions or effects that are affecting any of them now affects the unified form. 

Each Kobold has an unarmored AC equal to 11 + Dex modifier. They can use a shield and still gain this benefit. 

Each Kobold has a strength score of 7 while scattered.

You can use your reaction to activate Scatter! when hit by an attack that targets only you, causing the attack to miss. You can use this trait a number of times equal to your proficiency bonus, and you regain all expended uses when you finish a long rest.

You have learned to pass yourself off as one being, rather than several. If another creature becomes suspicious of your identity, they can make an insight check against your passive deception (8 + proficiency bonus + Charisma) to discern the nature of your being. If they equal or exceed your score, they recognize that you are wearing a disguise. If they exceed it by 5 or more, they realize you are three kobolds in a trench coat. If they do not meet your passive deception, they believe you are who you say you are, and can't make this check again unless you act strangely (at DM's discretion).

You have proficiency with a disguise kit, which is included with this race.

Your character can speak, read, and write Common, Draconic, and one other language per Kobold that can be used to maintain your secret identity.