By sacrificing your movement & bonus action you are allowed to take 1 extra action on your turn.

==Extra Action Guidelines==
  * Any dice you roll with this extra action will have disadvantage.
  * If you are holding concentration on a spell when you take an extra action, then you have to roll to keep concentration before taking your extra action (You do not gain disadvantage for this concentration roll).
  * If an opponent must make a saving throw against your action, then they gain advantage for that saving throw.