Champion's Blade

you touch a weapon within range, that deals slashing damage. until the spell ends, it deals an additional 1d10 damage on a hit, you get a critical hit on a 19 or 20, and, as a bonus action, you can will the weapon to turn into any other, non-magical weapon that deals slashing damage. additionally, when you take the attack action to attack with the weapon, you may use your bonus action to make another melee attack with the weapon. 

while holding the weapon, if you are targeted by a melee attack, you may use your reaction to gain a plus 2 bonus to your AC.