You can call upon your "magic" to cast "Cantrips" in combat. Once on each of your turns when you hit a target with a Strength-based attack, you can use one of the following "Cantrips" of your choice.
Mage Hand
You can push the target up to 5 feet straight away from yourself if it is Large size or smaller. While your XPHB is active, you can push the target up to 10 feet instead.
Shocking Grasp
The force of your strike is quite shocking. The target can't make Opportunity Attacks until the end of the current turn. While your XPHB is active, it can't make Opportunity Attacks until the start of your next turn.
True Strike
You really, truly strike, dealing an extra 1d6 damage to the target. The damage has the same type as the weapon or Unarmed Strike used for the attack. While your XPHB is active, you add half your Barbarian level (round down) to the extra damage.