Arcane Cannon: Lightning Shot

It takes one action to aim the cannon and one action to fire it. After the cannon has fired, it must recharge for 5 minutes before it can be fired again.

Lightning Shot. The cannon shoots a ball of lightning to a point you can see within 1,200 feet of the cannon. The lightning then expands to form a 20-foot-radius sphere centered on that point. Each creature in that area must make a DC 15 Dexterity saving throw, taking 33 (6dl0) lightning damage on a failed save, or half as much damage on a successful one. Creatures wearing metal armor have disadvantage on the save.