A monster with darkvision can see in the dark within a specific radius. The monster can see in dim light within the radius as if it were bright light, and in darkness as if it were dim light. The monster can't discern color in darkness, only shades of gray. Many creatures that live underground have this special sense.

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

Arachne has advantage on Strength (Athletics) and Dexterity (Acrobatics) checks

Arachne has advantage on attack rolls against a creature she is grappling, and she can grapple creatures up to two sizes larger than her. In addition, she can use her bonus action to try to pin a creature she has grappled. To do so, she makes another grapple check. On a success, the creature is restrained until the grapple ends.

You can cast the spell web a number of times equal to your overall level. You regain all uses when you finish a short or long rest.

Arachne can climb difficult surfaces, including upside down on ceilings, without needing to make an ability check.

While in contact with a web, Arachne knows the exact location of any other creature in contact with the same web.

Arachne ignores movement restrictions caused by webbing.

Arachne can generate venom from the glands in her body. She can make either a less-than-lethal paralytic venom or a deadly toxin as many times as equal to her overall level. The affected target must make a constitution saving throw to resist being poisoned.