Fighting Styles
Skirmish
When you make a melee attack against a creature, you don't provoke opportunity attacks from that creature for the rest of the turn, whether you hit or not.
You can also give yourself advantage on a weapon attack roll against a creature that cannot take a reaction (either because it has already used its reaction or because it is denied a reaction) once on your turn.
You do not gain these benefits if you wear heavy armour.