Combat Expertise

You evolved into fighting with weapons, gaining the following benefit:

• In the begin of your turn you can choose to take a penalty to the attack rolls up to you proficiency bonus. If the attack hits, you add doble of that to the attack's damage.
• additionally in your turn you can you can instead choose to take a penalty to the attack rolls up to you proficiency bonus, and add half of that to you AC, till your next turn.