Arcane Tempest

You channel yourself as a conduit of raging arcane power. Any creature within 60 foot sphere around you needs to perform a constitution saving throw or take 10d6 lightning damage. For any creature that takes that damage, roll a percentile dice. With a 60% or above, a spark of arcane energy jumps off to another target outside of the 60 foot sphere.

Until the end of your next round, the 60 sphere around you is considered difficult terrain.

At Higher Levels. When you cast this spell using a spell slot of 6th level or higher, the damage increases by 1d6 for each slot level above 5th.