Blue Spider

Dark Web. The spider gains a +4 bonus to attack and damage rolls against any creature restrained by its web attack.

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

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

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

Bite. Melee Weapon Attack: +5 to hit, reach 5 ft., one creature. Hit: 9 (2d4 + 3) piercing damage, and the target must make a DC 12 Wisdom saving throw, or become frightened for 1 minute. A creature can repeat the saving throw at the end of each of its turns, ending the effect on itself on a success. If a creature's saving throw is successful or the effect ends for it, the creature is immune to this effect for the next 24 hours.

Web (Recharge 5–6). Ranged Weapon Attack: +4 to hit, range 20/60 ft., one creature. Hit: The target is restrained by webbing. As an action, the restrained target can make a DC 12 Strength check, bursting the webbing on a success. The webbing can also be attacked and destroyed (AC 10; hp 5; vulnerability to fire damage; immunity to bludgeoning, poison, and psychic damage).