Persistent Lightning

7th-level evocation

Casting Time: 1 action

Range: 150 feet

Components: V, S, M (a rod of amber, crystal, or glass)

Duration: 1 minute

You create a bolt of lightning that strikes a target you can see within range. The target must make a Dexterity saving throw. On a failure, the target takes 10d8 lightning damage, and the lightning persists (see below). If the saving throw succeeds, the target takes half as much damage and the lightning doesn’t persist. The target can repeat the saving throw at the end of each of its turns, ending the effect on itself on a success.

If the lightning persists, each time the target moves, takes damage, or uses an action, a bonus action, or a reaction, it takes 2d8 lightning damage. In addition, once per round when the target takes lightning damage, a bolt of lightning arcs from the target to the closest creature within 30 feet. That secondary target must succeed on a Dexterity saving throw or take 2d8 lightning damage. The target and secondary targets have disadvantage on saving throws against this spell if they are wearing metal armor or made of metal.