Bladesworn

You’ve sworn to the blade, and you are one with the blade. You gain the following benifits

• You gain proficiency in martial weapons 
• a number of times equal to your proficiency bonus, you can launch a single precise attack. This attack cannot miss, and deals 3d12 slashing damage, but you cannot take bonus actions, reactions, or free actions for 3 rounds. You also cannot use this feature again until 3 rounds have passed, and taking this action instantly ends your turn.