Dojor's Electric Chair

An incredibly fast flash of lightning streaks from the rod, striking up to 3 creatures within range. Lightning forms a cage of pulsating electricity around the chosen creatures, keeping them inside a 5ft energy cage. Each target must make a dexterity saving throw, on a failure, the creature takes 7d8 (35) lightning damage and are restrained for 1 minute, on a successful save, the creature takes half as much damage and is not restrained. At the end of their turn, a targeted creature may use an action to attempt to escape the spell, it must make a Constitution Saving throw against the caster's spell save DC. 

If a creature moves within 5ft of a cage for the first time on a turn or starts its turn there, they take 1d6 (4) lightning damage. An uneffected creature may use an action to attempt to free a creature from the spell, they must make a strength saving throw against the caster's spell save DC.

At Higher Levels. When you cast this spell using a spell slot of 6th level or higher, the number of creatures you can target increases by 1 and creatures that move within 5ft of a cage for the first time on a turn or starts its turn there take an addional 1d6 per spell level.