Armor Class 18 (natural armor)
Hit Points 310 (20d20 + 150)
Speed 50 ft., climb 50 ft.
Condition Immunities charmed, exhaustion, frightened
Senses blindsight 30 ft., darkvision 120 ft., passive Perception 11
Languages —
Challenge 18
Legendary Resistance (3/Day). If the spider fails a saving throw, it can choose to succeed instead.
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.
Multiattack. The spider makes two Bite attacks. It can replace one of these attacks with a use of Web Bomb.
Bite. Melee Weapon Attack: +14 to hit, reach 20 ft., one target. Hit: 19 (2d10 + 8) piercing damage plus 7 (2d6) poison damage.
Web Bomb. Ranged Weapon Attack: +14 to hit, range 300 ft./600 ft., one target. Hit: 24 (3d10 + 8) bludgeoning damage, and the target and all creatures within 10 feet of it must succeed on a DC 19 Dexterity saving throw or take 10 (3d6) acid damage and have the restrained condition until the start of the spider's next turn.
Absorb Blow. In response to being hit with an attack roll, the spider's carapace absorbs some of the blow, reducing the damage it takes by 11 (2d10).
VEoR, p. 214