Opportunist

You can seize upon every opportunity in battle when your enemies drop their guard. You gain the following benefits:

• Once per round, you can make an opportunity attack without using your reaction, though you cannot make more than one reaction on the same turn.
• You can make an attack of opportunity against any creature within your reach that:
  • Tries to pick up, or grab an item.
  • Stands up from a prone position.
  • Attempts to shove or grapple you.
  • Is within 5 feet of you and attempts to move without disengaging.