Instead of just picking a race, you choose 3 abilities, which can represent your ancestry or background, and are organized into helpful categories.

You can also choose these abilities as feats. Some abilities require rank 2 or higher--they can only be taken as feats.

Humanoid

Orcish Battle-rage: Once per encounter, gain your proficiency bonus again to melee damage, and the same amount of Damage Reduction. Lasts 3 rds.
Gift of the Eldar: Encounter, swift; you call upon nature for a minor favor, such as changing the direction of the wind, aiding or hindering natural concealment, a small temperature change, etc.
Cast-Iron Stomach: The Earthen races, such as Dwarves, are known for their impressive fortitude. You gain resistance to disease and poison damage, or advantage to saves against disease and poison when non-damaging.
Elf Step: When moving over natural terrain, you don't leave tracks, nor make sounds with footsteps, nor are you slowed by natural difficult terrain.
Northern Born: Resist cold 50%, ignore natural cold environmental penalties.
Shadowmeld: In any area of natural foliage that grants partial concealment, you can become invisible while immobile. etc...

Sylvan

Eagle Eye: You have super-fine sight. Gain advantage to certain Perception checks, etc.

Aquatic Nature: Your true form is a water creature, although you can take humanoid form at will. In your true form, you gain water breathing, a swim speed of 40 ft, etc.
Glamour: At-will, you can assume an enchantment that enhances your appearance in both visual and magical ways, rendering you unusually attractive and captivating. You gain advantage to any Charisma check for which this would apply (e.g. it is useful for most Persuasion checks, but not so much for Intimidate).
Siren Song: Your voice is enchanting beyond mortal constraints. You gain advantage to any Perform checks involving your voice. Also, choose one Bardic Music feat, such as Fascinate, Inspiring Song, etc. You can do that too.

Born in Flames: Gain resist 50% fire.
Firestarter: You can shed flames at will. Add your proficiency bonus as bonus fire damage to unarmed attacks. Enemies who strike you with natural weapons suffer that amount of fire damage.
Infernal Chains: You can sprout spiked chains. You can wield them as a weapon (reach, 2h, heavy slashing, can grapple). You can use them as an offhand weapon (reach, 1h, medium damage).

Demon Wings: Gain the ability to slowfall and glide at will. While in use, batlike wings appear.

Blood Like Fire: Gain Immunity to Fire. Requires and replaces Born in Flames.
Wings of the Fallen: Gain a fly speed equal to walking speed. Requires and replaces Demon Wings.

Cloaked in Shadow: When an attacker suffers any level of concealment against you due to low light levels, you gain your proficiency bonus as a bonus to AC (against attacks) or saves against such attacks.
Withering Touch: Your touch drains life. Simply touching a plant or insignificant animal (such as an insect) withers and kills it. You may suppress this ability when not desired. As a melee touch attack, you can inflict medium necrotic damage plus 1d4 Con damage.

Psychic Symbiote: Your mind is host to an alien being, one made of pure thought and energy. You can have conversations with it; it shares your perceptions, but does not control your actions; it has alien knowledge that may be of use to you, but could also be horrifying or maddening to comprehend. Once per day, it can negate a failed mental save, taking the effect instead of you. Once per short rest, it can hold concentration on a mental action (such as maintaining a spell) in your stead, allowing you to use your concentration for something else.

Kiss of Death: At-will, Dex vs touch AC; light necrotic damage. 1/day/prof bonus, heal the dmg dealt, or gain the dmg dealt as a bonus to one check/save/attack.
Improved Kiss of Death: Kiss of Death inflicts heavy damage plus 1d4 Cha damage.