Defencive Stance

You have achieved learned that sometimes the best offence is a good defence, granting you the following benefits:

• Increase your Strength or Dexterity by 1, to a maximum of 20.
• Once per turn, you can use your action to enter a defencive stance gaining +3 to AC until the start of your next turn. If a creature attacks you and misses you may then use your reaction to make an attack of opertunity against this creature with advatage.