Tantrum

Temper
Temper is a powerful battleaxe forged by halflings and lost hundreds of years ago. If wielded by a non-halfling, and a nat 1 is rolled, you develop a fear of crit misses. All attacks, saves, and ability checks are made with disadvantage until the end of your next turn. You gain a +1 bonus to attack and damage rolls made with this magic weapon (+2 when dual wielded with Temper).

Thrown Weapon.
Temper has the thrown property, with a normal range of 20 feet and a long range of 60 feet. When you hit with a ranged weapon attack using it, the target takes an extra 1d8 lightning damage, or an extra 2d8 lightning damage if the target is a giant. Each time you throw the weapon, it flies back to your hand after the attack. If you don't have a hand free, the weapon lands at your feet.

Shock Wave.
You can use an action to bash the weapon into your chest and send a shock wave out from the point of impact. Each creature of your choice on the ground within 60 feet of that point must make a DC 14 CON save or become stunned (and prone) for one round. Once used this property can’t be used until the next dawn.

Berserker.
Once per long rest, while in battle, you can fight with primal ferocity. On your turn, you can enter a rage as a bonus action. While raging, have resistance to bludgeoning, piercing., and slashing damage. You also gain advantage on all attacks, but all attack have advantage against you until the end of your next turn.