Armor of Spiders (Mythic Trait; Recharges after a Short or Long Rest)
If Arasta is reduced to 0 hit points, she doesn't die or fall . Instead, she regains 200 hit points. In addition, Arasta's children immediately swarm over her body to protect her, granting her 100 temporary hit points.
Legendary Resistance (3/Day)
If Arasta fails a saving throw, she can choose to succeed instead.
Magic Resistance
Arasta has advantage on saving throws against spells and other magical effects.
Spider Climb
Arasta can climb difficult surfaces, including upside down on ceilings, without needing to make an ability check.
Web Walker
Arasta ignores movement restrictions caused by webbing.
Actions
Multiattack
Arasta makes three attacks: one with her bite and two with her claws.
Bite
Melee Weapon Attack+14 to hit, reach 5 ft., one creature. 20 () 🏹 Piercing damage, and the target must make a DC 21 Constitution saving throw, taking 32 () ☠️ Poison damage on a failed save, or half as much damage on a successful one. If the damage reduces the target to 0 hit points, the target is stable but for 1 hour, even after regaining hit points, and is while in this way.
Claws
Melee Weapon Attack+14 to hit, reach 5 ft., one target. 17 () 🗡️ Slashing damage.
Web of Hair Recharge 4
Arasta unleashes her hair in the form of webbing that fills a 30-foot cube next to her. The web is Difficult Terrain, its area is lightly obscured, and it lasts for 1 minute. Any creature that moves into the web or that starts its turn there must make a DC 21 Dexterity saving throw. On a failed save, the creature is while in the web. A creature can use an action to make a DC 21 Strength check. On a success, it can free itself or a creature within 5 feet of it that is by the web. This webbing is immune to all damage except magical fire. A 5-foot cube of the web is destroyed if it takes at least 20 🔥 Fire damage from a spell or other magical source on a single turn.
Legendary Actions
Claws
Arasta makes one attack with her claws.
Swarm (Costs 2 Actions)
Arasta causes two to appear in unoccupied spaces within 5 feet of her.
Toxic Web (Costs 3 Actions)
Each creature by Arasta's Web of Hair takes 18 () ☠️ Poison damage.
Mythic Actions
Swipe
Arasta makes two attacks with her claws.
Web of Hair (Costs 2 Actions)
Arasta recharges Web of Hair and uses it.
Nyx Weave (Costs 2 Actions)
Each creature by Arasta's Web of Hair must succeed on a DC 21 Constitution saving throw, or the creature takes 26 () 🌀 Force damage and any spell of 6th level or lower on it ends.