Vikavolt (5e Creature)
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Medium monstrosity, any alignment
Battery. All creatures of the vikavolt's choice within 30 feet of it have advantage on spell attack rolls.
Swarm. While it has 50 hit points or fewer, the vikavolt has advantage on attack rolls. In addition, it deals an extra 7 (2d6) damage to any target it hits with an attack.
Thunderbolt. Ranged Spell Attack: +8 to hit, range 80/320 ft., one target. Hit: 22 (5d6 + 5) lightning damage.
Signal Beam. Ranged Spell Attack: +8 to hit, range 80/320 ft., one target. Hit: 15 (3d6 + 5) radiant damage. If the target is a creature, it must succeed on a DC 16 Wisdom saving throw or be stunned until the end of its next turn.
Arc Bolt. When a creature hits the vikavolt with a melee attack, it can use its reaction to deal 9 (2d8) lightning damage to the attacker.