When a creature makes a melee attack, it can also mark its target. Until the end of the attacker’s next turn, any opportunity attack it makes against the marked target has advantage.
The opportunity attack doesn’t expend the attacker’s reaction,
The attacker can’t make the attack if anything, such as the incapacitated condition or the shocking grasp spell, is preventing it from taking reactions.
The attacker is limited to one opportunity attack per turn.
When a creature makes a melee attack, it can also mark its target. Until the end of the attacker’s next turn, any opportunity attack it makes against the marked target has advantage.
The opportunity attack doesn’t expend the attacker’s reaction.
If the marked target attacks a creature other than you, you may take a melee weapon attack against them.
The attacker can’t make either of these attacks if anything, such as the incapacitated condition or the shocking grasp spell, is preventing it from taking reactions.
The attacker is limited to one opportunity attack per turn.
When you make a Dexterity (Stealth) check or an initiative roll, you can expend one superiority die and add the die to the roll, provided you aren't incapacitated.
When you're within 5 feet of a creature on your turn, you can expend one superiority die and switch places with that creature, provided you spend at least 5 feet of movement and the creature is willing and isn't incapacitated. This movement doesn't provoke opportunity attacks.
Roll the superiority die. Until the start of your next turn, you or the other creature (your choice) gains a bonus to AC equal to the number rolled.