A wand made up of several lightning-struck branches from an
assortment of different tree species, it's capable of turning an
otherwise mediocre spell into a potent force.

Witch Bolt: The spell can be augmented in the following
ways. You can choose as many of the options as you like, but
must use an additional charge of the wand for each.

• If the target tries to move outside the range of the spell it
  must make a contested Strength check versus the caster's
  spellcasting ability modifier. On a failure, the target's speed
  is reduced to 0 until the start of their next turn.
• The attack roll has advantage against targets that are
  wearing armor made of metal, or that are of the plant
  creature type.
• You add your spellcasting ability modifier to both the initial
  and subsequent damage rolls of the spell.
• If any other creatures are between you and the target when
  you deal automatic damage to it, they must make a
  Dexterity saving throw or take the same amount of
  damage, or half as much on a success.
• The target having total cover from you no longer ends the
  spell, but you must make a DC10 Constitution saving
  throw to maintain concentration if you start your turn with
  your target in total cover. The DC increased by 1 each time
  you succeed on this save.
• The automatic damage of the spell becomes 3d4, and
  increases by 1d4 each time you deal automatic damage.