Been enjoying the Battle Master Fighter, but have a question about use of maneuvres with the two parts of Polearm Master:
When you take the Attack action and attack with only a glaive, halberd, or quarterstaff, you can use a bonus action to make a melee attack with the opposite end of the weapon. This attack uses the same ability modifier as the primary attack. The weapon’s damage die for this attack is a d4, and it deals bludgeoning damage.
While you are wielding a glaive, halberd, pike, or quarterstaff, other creatures provoke an opportunity attack from you when they enter your reach.
On the first part, can a maneuvre be used as part of the melee attack with the shaft of the weapon? You cannot (mostly) use two maneuvres on a single attack, however does this Bonus Action constitute a new attack? If so I am also assuming the main halberd attack is resolved first and then the bonus action. So I couldn’t use the bonus action to attempt a trip with the shaft, then if successful attack with the halberd itself at advantage.
On the second part I can use my reaction to attack a creature that comes within my reach. Can I then apply some of the maneuvres to this attack? This is focused on the wordings being different, so for example:
Immediately after you hit a creature with a melee weapon attack on your turn, you can expend one superiority die and use a bonus action to grapple the target (see chapter 9 in the Player’s Handbook for rules on grappling). Add the superiority die to your Strength (Athletics) check. The target is also restrained while grappled in this way.
"On your turn" clearly means that I couldn’t perform this using a Reaction. However to compare:
When you hit a creature with a weapon attack, you can expend one superiority die to attempt to knock the target down. You add the superiority die to the attack’s damage roll, and if the target is Large or smaller, it must make a Strength saving throw. On a failed save, you knock the target prone.
That makes no reference to the attack being on my turn, so if an opponent charged towards me I could use Polearm Master to initiate a Reaction. On a hit, can I use a Maneuvre that only requires a "weapon attack" as part of this Reaction?