Spider Climb. The spider can climb difficult surfaces, including upside down on ceilings, without needing to make an ability check.

Web Walker. The spider ignores movement restrictions caused by webbing.

Invisible Webs. The spider spins invisible webs that can't be seen by normal vision. Any ability or spell that reveals invisible things will show the webs. 

Web Sense. The spider is Blind and Deaf relying instead on a creature to walk into their invisible webs to know where they are. The webs are incredibly fragile and anything that touches it, other than the spider, will break it.

Bite. Melee Weapon Attack: +4 to hit, reach 5 ft., one creature. Hit: 7 (1d10 + 2) piercing damage, and the target must make a DC 11 Constitution saving throw, taking 9 (2d8) poison damage on a failed save, or half as much damage on a successful one. 

Teleport. As a bonus action, the spider can teleport from its current space to another unoccupied space within 60ft. of it.