Blessed by the black sparks

You have been blessed by the black sparks when ever you hit a creature with a melee attack you may infuse the power of the black sparks to deal more damage when doing this it looks as if black and red lightning shoots off of the melee weapon being use or your fists

you can black flash 4 times per long rest which adds 2d4 lightning damage to any melee attack It can't be used on the same creature again

AT HIGHER LEVELS 

when using this feat, damage die changes. level 8 2d6, level 12 2d8, level 16 2d10, level 19 2d12.