Swarm Coordination. If there are two or more Voidweavers within 5 feet of the same target, they gain advantage on attack rolls against that target.

Energy Drain. The Voidweaver’s melee attacks siphon magical energy. On a hit, the target takes 1d6 necrotic damage, and if the target is a spellcaster, they must succeed on a DC 12 Constitution saving throw or lose 1 spell slot of the highest level they can cast (if applicable).

Plane Shift Escape (Recharge 6). If the Voidweaver is reduced to 10 hit points or fewer, it can use its reaction to attempt to shift back through the rift, disappearing into the void. It rolls a d6, and on a 5 or 6, it vanishes and reappears 30 feet away.

Multiattack. The Voidweaver makes two attacks: one with its Energy Drain and one with its Tendril Strike.

Energy Drain. Melee Weapon Attack: +4 to hit, reach 5 ft., one target. Hit: 1d6 necrotic damage, and if the target is a spellcaster, they must succeed on a DC 12 Constitution saving throw or lose 1 spell slot of the highest level they can cast (if applicable).

Tendril Strike. Melee Weapon Attack: +4 to hit, reach 5 ft., one target. Hit: 2d6 necrotic damage. On a critical hit, the Voidweaver can pull the target 5 feet closer to itself.

Void Lash (Recharge 5–6). The Voidweaver lashes out with a wave of void energy in a 10-foot line. Each creature in the line must make a DC 12 Dexterity saving throw, taking 2d6 necrotic damage on a failed save, or half as much damage on a successful save.

• Void Flicker. The Voidweaver can momentarily phase between dimensions, evading attacks. Until the start of its next turn, the Voidweaver has advantage on Dexterity saving throws and disadvantage on attack rolls made against it.

• Energy Surge. The Voidweaver channels more power into its next Energy Drain attack. The next time it hits with Energy Drain before the end of its turn, it deals an additional 1d6 necrotic damage.

• Rift Pulse. The Voidweaver pulses with rift energy, disrupting the flow of magic around it. Each creature within 5 feet of the Voidweaver must make a DC 12 Constitution saving throw. On a failed save, a creature has disadvantage on its next spell attack roll or concentration check.

Energy Absorption (Magical Attack).
When the Voidweaver is targeted by a spell that deals damage, it can use its reaction to absorb some of the energy. The Voidweaver regains hit points equal to half the damage dealt by the spell, up to a maximum of 5 hit points.
Flavour: The rift flickers, drawing magical energy into the Voidweaver’s form to replenish its vitality.

Teleport (Costs 1 Action). The Voidweaver teleports up to 15 feet to an unoccupied space it can see.