Your Dexterity increases by +2, your Intelligence +1

Mature at 18, Ythiil have a long life-span living well into their 500s.

Societally, the Ythiil have strict rules and regulations about perfection. They are lawful neutral, willing to do anything to keep their populace in check. However, adventurers tend to be of wide varieties of alignment.

Ythin, Common, Undercommon

You have superior vision in darkness and can see up to a radius of 120 feet in darkness.

You have four (unless you’ve lost one for some reason) hands and limbs that move independently of one another (six if you include your legs). For these purposes, you are able to cast somatic components even whilst holding both a weapon and shield without the need for a feat like Warcaster. You cannot, however, carry more weapons than would be normal without at least a Strength score of 18 to properly bear the weight of all your items, unless they are all lightweight in status.

Ythiil come in three different subraces, each of which has a different roll in their society. Comet Ythiil tend to be the main denizens. Your tradesman, crafters and artisans. Death's Head Ythiil are soldiers, the fighters and grunts even amongst the elite. Finally, Luna Ythiil are considered the nobility and royalty of these creatures. They are treated with reverence when crossing paths with most denizens.

Comet Ythiil

Making up the majority of the main denizens of inner Ythiilian society, the Comet variation of Ythiil are bright yellow in coloration. The females tend to be larger than the males, though these concepts of gender do not prescribe to this inner culture and is only in terms of categorized sex of other species. Gender is not a concept as it flies in the face of the “sameness” that Ythiilian society deems appropriate for their species. This means that predominantly Ythiil presented with gender in adventuring tend to be confused and not understand why different clothing would mark one as one or the other.

Ability Score Increase

 you gain a +1 to your Constitution Score

Frequent Faster

Comet Ythiil do not require the same amount of sustenance as most creatures. You do not need to eat or drink as often as most creatures, instead only growing hungry after five days of fasting.

Breathless

You do not require as much air as some creatures. You can go without breathing for as many minutes as your Constitution Score.

Death's Head Ythiil

The soldiers of the Ythiilian race tend to be more jaded than their inner-city counterparts. They know the truth of their society, so many of the adventurers are actually this subspecies. They tend to be brawnier than others but some can be powerful spellcasters as well. Death’s Heads are trained for combat from the age of ten and up. 

Ability Score Increase 

+1 to Strength

Intimidating Display

Due to the distinctive skull-like pattern on the back of their heads and their strange, shriek-like battle cry, the Death’s Head Ythiil has advantage on any intimidation check that they make after they spread their wings and let out a ghastly scream as a bonus action. You may use this ability a number of times equal to your level before taking a long rest. In addition you automatically have proficiency in the Intimidation skill.

Weapon Proficiency

Your race is trained in combat from a very young age. You are proficient in wielding the following weapons: maces, flails and morningstars.

Luna Ythiil

Those with considered the highest in Ythiilian society, the Monarchs and resulting royal bloodlines as well as nobility, Luna Variants are hard to find as adventurers. But that does not mean they are an impossibility. Even nobility finds a reason to flee from their lives at times. Who knows. Either way, these are the only denizens of Ythria that are trained in diplomacy.

Ability Score Increase 

+1 to Charisma

Sightless Confusion

When dealing with a creature that has blindsight or tremorsense, creatures that are standing within 10 feet of Luna Ythiil treat that creature as if it had the blinded condition without those features.

Luminescence

You have the ability to light your wings when in dark places, shedding dim light that does not affect your light sensitivity for up to 20 ft at will.