Does the Disarm action optional rule (DMG) make the Disarming Attack maneuver (Battle Master fighter) useless?

Question

I would like an analysis of this with feedback.

Does the Disarm combat option (DMG, p. 271) make the Disarming Attack maneuver (PHB, p. 74) useless by being the better option?

Here are the pros & cons of each so far.

Disarm action optional rule:

1. Uses attacker's attack roll vs. defender's Athletics (Str) or Acrobatics (Dex). (Of 123 monsters with weapons, only 8 have proficiency with those skills and 3 of those are giants, so possibly not disarmable.)

2. Size of creature and type of weapon give adv/disadvantage.

3. Can always be used as long as you have a weapon attack.

Disarming Attack maneuver pros/cons:

1. Is applied on a hit with a weapon.

2. Does extra damage along with the disarming effect.

3. Target must make a strength save to resist the effect. Of 123 monsters with weapons, only 11 have proficiency with strength saves.

4. Target size and weapon type does not matter

5. Has limited uses.

Answer 1

No. Disarming Attack isn't useless.

Here's my reasoning:

To determine if the Disarm option makes the Disarming Attack battlemaster maneuver useless, we need to compare a situation where either one or the other could be used — that is, whether a fighter who can make a Disarming Attack is always better off attempting a Disarm instead.

I took some stats for a typical 3rd-level Battlemaster fighter: AC 18, 34 HP, +6 attack for d8+6 damage, DC14 for saves vs. their maneuvers. I then looked at a few CR 1/2 - 2 creatures and the expected results when the fighter attempted a Disarm against the creature vs. the results when she used Disarming Attack.

Note that a creature that doesn't have Athletics or Acrobatics proficiency doesn't automatically lose the Disarm contest; they just use their Strength or Dexterity modifier instead. So it's not really accurate to say (as expressed in the question) that those creatures don't have the skills to defend themselves. Likewise, all creatures have a Strength saving throw, and have a chance to save against Disarming Attack.

Generally speaking:

• Disarm has a much higher chance of success (in the 50-70% range ), since it doesn't require a successful hit first.

• Disarming Attack has a much lower chance of actually disarming the creature (in the 25-35% range), since it requires the attacking fighter to first overcome the creature's AC, and then for the creature to fail its saving throw.

The other tradeoffs between the two are enumerated in the question itself; the most significant of these is that Disarm does no damage, and Disarming Attack always does above-average damage (due to the superiority die) on a hit, even if the target isn't disarmed. This means that the basic comparison between the two options is that Disarm has a high chance of disarming but never does damage while Disarming Attack has a lower chance of disarming but does above-average damage.

So the key question is: under what circumstances is it more useful to disarm an opponent than just do damage to them? Bear in mind that causing a creature to drop one of the weapons it's holding doesn't mean it's no longer a threat. Many creatures carry multiple weapons, or have natural attacks such as biting that can't be disabled with a disarm. Creatures can also slam or grapple, or try and recover their weapon, or even attempt to disarm their attacker.

One scenario where Disarm might be useful is against hard-hitting creatures with moderate hit points. A bugbear is a typical example; their attack does a lot of damage, but their hit points aren't so low that it's safer to just try and kill them quickly. A successful Disarm attempt will reduce the threat they pose and buy the fighter some extra time to chip away at their hit points (assuming it takes the bugbear on average more than one turn to recover from being disarmed). This isn't the case against a creature like an orc, with fewer hit points; our fighter is probably better off using Disarming Attack (which, if it hits, has a good chance of killing the orc outright) or just making regular attacks. And against a higher-CR creature with more hit points, like a Bandit Chieftain, the couple of rounds that a Disarm might buy the fighter isn't enough to offset the creature's higher hit point total significantly.

Combat situations can vary greatly, of course, at at higher character levels and monster CRs it becomes much harder to model. I think it is safe to say, however, that because it doesn't deal any damage, Disarm isn't always going to be a better choice than Disarming Attack for a character who can use either one.

Answer 2

Not at all. As you yourself note, it combines the disarm with a damaging weapon attack, combining the two into one. This makes for good action economy, which is the single greatest factor in who wins combat. And the outcome of combat is often decided in a single round. A well-chosen maneuver (or two or three) will often make that decisive round happen on your terms.

Answer 3

You can't compare them

The "Disarm" action is not exactly a variant rule, but a combat option. Combat options are described in the DMG as "alternative ways to handle combat". That is to say, "Disarm" action mechanics is mostly for a DM, that's why it is not described in the PHB.

In its turn, PHB has the improvised action description:

Improvising an action

Your character can do things not covered by the actions in this chapter, such as breaking down doors, intimidating enemies, sensing weaknesses in magical defenses, or calling for a parley with a foe. The only limits to the actions you can attempt are your imagination and your character's ability scores. See the descriptions of the ability scores in chapter 7 for inspiration as you improvise.

When you describe an action not detailed elsewhere in the rules, the DM tells you whether that action is possible and what kind of roll you need to make, if any, to determine success or failure.

Characters can attempt to make any actions they want. A player can say "I am trying to knock the lantern out of his hand". In this case the DM can use the existing mechanics from the DMG:

A creature can use a weapon attack to knock a weapon or another item from a target's grasp.

Alternatively, DM can use a different roll, or just say what happens, without any rolls.

On the other hand, the Disarming Attack maneuver is described in the PHB as a strict class mechanics. It is a distinctive feature of the Battle Master archetype, which the Fighter player should be aware of. In their turn, the player should reference to this exact maneuver, in orter to be sure how it will work mechanically.

Disarming Attack. When you hit a creature with a weapon attack, you can expend one superiority die to attempt to disarm the target, forcing it to drop one item of your choice that it's holding

That's it - when you hit you can say "I expend a superiority die" and disarm the opponent. You say it as a player to the DM, not as your character.

The main mechanical difference

Of course, before the game starts, the DM can say "I use an optional rule for disarming. Any character can disarm an opponent with an attack roll". In this case the Disarming Attack maneuver still has a major advantage.

A player announce the Disarming Attack maneuver after the attack roll, and the common Disarm action before the attack roll.

When you announce the Disarm action you forgo any other action and still can miss, effectively wasting the action. In contrast, when the Battle Master's attack hits, they can announce the Disarming Attack maneuver. Keep in mind that the Fighter class also has the Extra attack feature.

Answer 4

Action Economy

The DMG disarm is an Action (it is in the Action Options section of the rulebook). If you use it then you have not taken the Attack Action so features like Extra attack do not apply.

The disarm maneuver is an Attack. If you have multiple attacks from a feature like Extra Attack then you can attempt to disarm someone once for each attack.

You can use the maneuver with an opportunity attack.

Damage

The disarm action doesn't do damage. The maneuver does.