You have snake-like fangs. They are finesse weapons and deal piercing damage equal to 1d6 + your Dexterity modifier. On a hit, the target makes a con. Save, taking 2d4 poison damage on a failed save, and no damage on a succesful one. This damage scales to 3d4 (level 5), 4d4 (level 11), and 5d4 (level 17).

Your Dexterity score increases by 2, and your Intelligence score increases by 1.

Yuan-ti abominations tend to age at the same rate as humans.

Most yuan-ti abominations are Lawful Evil, though some adopt a softer view of morality once they leave their morally-oppressed enclaves.

Yuan-ti abominations vary widely in height and build, from barely 6 feet to well over 7 feet tall. Your size is Medium.

You have a form of heat-based perception resembling darkvision. 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.

You have an unarmored armor class of 13 + your dexterity modifier.

You have advantage on saving throws against spell effects.

You are resistant to poison damage and you have advantage on saving throws against being poisoned.

You can speak, read, and write Common and Yuan-Ti.