Your Strength or Constitution score increases by 2.

Your Intelligence score increases by 1.

You are a Humanoid.

Serpentine features: One part of you is identical to that of a snake, and has a unique ability. This can either be your head, arms or tail.

Snake Head:
You can spit venom at a target within 10 feet, dealing 1d6 poison damage on hit. The target must also make a Dexterity saving throw (DC 6+Strength modifier+proficiency bonus) or become blinded for their next 2 turns.

Snake Arms:
You can bite a target you can touch with an arm ending in a snake head, dealing 1d4 poison damage on hit. With your other arm, you can attempt to grapple a target, causing them to make a Dexterity saving throw (DC 7+Strength modifier+proficiency bonus), becoming grappled on a failure.

Snake tail:
Instead of legs, you have a large twisting serpentine tail. Your base walking speed increases to 35 feet, and it can be used to manipulate nearby items that weigh less than 5 lbs within 10 ft. of yourself. You can’t use your tail to perform complex tasks such as using tools, wielding weapons, or using items with it.

Your tail is a natural weapon which you are proficient with, which can be used to make unarmed attacks. If you hit with it, you deal bludgeoning damage equal to 1d6 + your Strength modifier. Alternatively, your tail may be used to make an attack action to grapple a creature. They must make a Dexterity saving throw (DC 8+Strength+Proficiency bonus). Upon failure, The creature is left constricted by your coiled tail until they succeed on a contested grapple check on their next turn to escape. Once the creature is restrained, on your next turn, you can use a bonus action to constrict the creature, dealing 1d6 bludgeoning damage.

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 discern colors in that darkness only as shades of gray.

You have advantage on saving throws you make to avoid or end the poisoned condition on yourself. You also have resistance to poison damage.

You know the poison spray cantrip. You can cast animal friendship an unlimited number of times with this trait, but you can target only snakes with it. Starting at 3rd level, you can also cast suggestion with this trait. Once you cast it, you can’t do so again until you finish a long rest. You can also cast it using any spell slots you have of 2nd level or higher.

Intelligence, Wisdom, or Charisma is your spellcasting ability for these spells when you cast them with this trait (choose when you select this race).

A Yuan-Ti can live roughly as long as humans, with few getting older than 150 years.