Chain Reaction

You unleash a series of explosive blasts that ripple through the battlefield. Choose up to three creatures you can see within range. Each target must make a Dexterity saving throw against your spell save DC. A creature takes 3d6 fire damage on a failed save or half as much damage on a successful one. If a creature fails its saving throw by 5 or more, it triggers another explosion that affects all creatures within a 5-foot radius of the initial target (excluding the initial target), forcing them to make a Dexterity saving throw against your spell save DC and take the same damage as the initial target on a failed save, or half as much on a successful one.