Your Dexterity score increases by 2, & you can choose another ability score to increase by 1.

Arachnae mature at the same rate as dark elves.

Arachnae are about the same size and build as dark elves. Your size is Medium.

Your base walking speed is 35 feet.

Thanks to your abyssal and drow heritage, 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.

You have resistance to poison damage and advantage on saving throws vs poison. In addition, you are immune to the poisoned condition.

You have a climbing speed equal to your walking speed. In addition, you can move up, down, and across vertical surfaces and upside down along ceilings, while leaving your hands free.

Your fangs are natural weapons, which you can use to make unarmed strikes. If you hit with them, you deal poison damage equal to 1d4 + your Constitution modifier, instead of the bludgeoning damage normal for an unarmed strike.

You can speak, read, and write Common and Undercommon.

Your spider heritage endows you with four extra arms. These arms are in line below your two main arms. They can manipulate objects, open and close doors or containers, wield a shield or weapons.

You have eight eyes (two large main eyes with six smaller eyes arranged above, below, and to the sides). This allows you almost 360 degree vision, thus you can't be surprised while you are conscious. Also, you gain advantage on any perception check that relies on vision.

You have advantage on saving throws against being charmed, and magic can’t put you to sleep.