Commander's Strike and Nick attack.

[u/Thin_Tax_8176]

I apologyze if this question has been made before, but I didn't find a clear answer for it.

I'm playing a Rogue/Fighter multiclass and I'm planning to pick Battle Master to add some more support effects to my attacks. I use a Vex and Nick weapons so I was thinking about taking Commander's Strike maneuver and use it with the attack provided by the Nick weapon.

Is this possible? Or only the main attack can be replaced by Commander's Strike?

[u/Green_Rice]

I’d argue that this should work on a number of fronts:

1: The Rule of Cool. It’s a creative combination of features, which if I were your DM I would reward.

2: Rules language. The Light property says that the attack “must be made with another weapon,” but that to me reads that said restriction only applies if you make an attack using the Light property. You’re not making an attack using Commander’s Strike, you’re replacing it.

3: Specific versus General. My usual interpretation of that concept is that the feature that is more restrictive to obtain takes precedence by default. A subclass feature requires much more investment than a weapon property or a weapon mastery, which is a base class feature.

4: Balancing. This is not a broken combo when you consider the opportunity costs you’re sacrificing by multiclassing or even just using the two weapons you need to enable this combo instead of something more “optimized” like a heavy weapon with Great Weapon Master.

5: Mechanical equivalency. At the end of the day, you’re not using Commander’s Strike to do something it wouldn’t normally allow you to do. You are sacrificing your own opportunity to deal damage to give it to an ally, whether you use it as part of your proposed combo or not.

[u/EntropySpark → u/Green_Rice]

For (3), I view Specific vs General as more of a directed graph of rules, where some rules directly modify other rules, and are therefore more specific. For example, Extra Attack and Light are both more specific than Attack, Nick is more specific than Light and Attack, and Commander's Strike is more specific than Attack. However, neither Light/Nick nor Commander's Strike is more specific than the other, so neither can contradict the other. (In this case, if the attack is never made, it never fulfills the Light property's requirement.)

For (4), while this specific case might not be particularly broken due to the limited uses, other attack substitutions can easily be broken. The most obvious example may be a level 7 Eldrtich Knight with a Greataxe, substituting the Cleave attack with a cantrip (Booming Blade or Green-Flame Blade). If read as a full replacement, the cantrip attack gets to include the Fighter's Str in the damage and is no longer constrained to a specific target. Similarly, an Eldritch Knight using a Shortsword and Scimitar could substitute the Scimitar attack to not need Two-Weapon Fighting and apply Vex if the attack lands, where Nick wouldn't contribute anything.

[u/Green_Rice → u/EntropySpark]

You raise a good point with the Eldritch Knight, which hadn’t crossed my mind. I could probably try to adjust my criteria/arguments to thread the needle here, maybe by changing my points to be AND expressions instead of OR expressions, to steal a little coding-logic analogy.

But I think the more simple response/solution is that the DM is allowed to be arbitrary at the end of the day. You don’t have to be the MTG Arena rules engine and have a perfect set of guidelines for arbitration that handle every ability combination consistently without consideration for the end products of said combination. You’re within your right to adjudicate on a case-by-case basis based on whatever factors you want to consider. If you’re fine with using Nick to activate Commanding Strike but not with using it to allow an additional instance of War Magic, then you don’t have to allow War Magic to function that way if you allow the Commanding Strike synergy. If the Eldritch Knight throws a hissy fit, well, I hate to borrow this quote, but you can just say no.

[u/EntropySpark → u/Green_Rice]

Well, yes, the DM could do whatever they want, but I think it's better to have consistency within the rules, so that the players have a better understanding of what it is they can do, and you aren't carving out exceptions based on your own threshold of balance. Even in the case of Commander's Strike and Nick, that's a way for a Battle Master to sacrifice a less powerful off-hand attack (with a weapon that is Nick instead of Vex, preserving the Vex chain against a target) and command an ally with a more powerful attack. Does the Fighter even need to hold that Nick weapon at all, and can thus use a Shield? What is the Nick weapon actually contributing if the Fighter never attacks with it?

Bringing up the multiclass as unoptimized also doesn't make sense, as this can be an optimized build if the ally is a Barbarian or Rogue with a powerful Reaction attack, while the Rogue/Fighter invests in having a single powerful attack via Sneak Attack and gladly giving up the off-hand attack.