You know the Dancing Lights cantrip. When you reach 3rd level, you can cast the Faerie Fire spell once with this trait and regain the ability to do so when you finish a long rest. Constitution is your spellcasting ability for these spells.

Driders range from under 7 to over 9 feet tall and half as wide. Your size is Medium.

Your base walking speed is 30 feet.

Increase one ability score by 2 and increase a different one by 1 or increase three different ability scores by 1.

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

You have Darkvision of 120 feet.

You have a climbing speed equal to your walking speed. In addition, at 3rd level, you can move up, down, and across vertical surfaces and upside down along ceilings, while leaving your hands free.

While in contact with a web, the spider knows the exact location of any other creature in contact with the same web. You ignore any Movement restrictions caused by webbing. Starting at level 5, you can cast Web once a day. Constitution is your Spellcasting ability.

You have advantage on Saving Throws against being Charmed, and magic can't put you to sleep.

While in sunlight, you have disadvantage on Attack rolls, as well as on Wisdom (Perception) checks that rely on sight.

Given your many legs, you have advantage on Saving throws to avoid falling prone. You count as one size larger when determining your carrying capacity and the weight you can push, drag, or lift.

You have proficiency with rapiers, shortswords, and hand crossbows.