Elemental blade

     You imbue a weapon with Elemental power Until the spell ends The weapon deals an extra 2d8 Damage in one of four elements Fire, Lighting, Cold, or Poison. If the weapon isn't already magic the weapon becomes so for the duration 

     As a bonus action the wielder of the sword and end the spell causing the blade to explode with the elemental energy. Each creature of your choice within 30ft must make a Constitution saving throw or take 4d8 of the chosen element type and Paralyzed until the end of the wielders next turn. on a successful save the creature takes half as much damage and isn't paralyzed.