Is this modified Dual Wielder feat balanced?

Question

The Issue

So, it is well known that the Dual Wielder feat is bad. Even if you are building a Two-Weapon Fighting character, the feat is still worse than simply getting straight-forward ASI. Unlike Polearm Master which is a go-to for someone using a Polearm, or Crossbow Expert for someone using a Crossbow, or GWM/Sharpshooter as good increase in DPR against low-AC enemies, plus some nice utilities (extra attack with bonus action, or almost-infinite range), the Dual Wielder is the last thing you are getting as a Two-Weapon Fighter (although you are probably still getting it, at least).

Furthermore, the Dual Wielder feat as is, for me, is boring. If I am playing a dual wielder I probably want to be dealing lots of damage, not have a +1 AC. And finally, Dual Wielder pretty much assumes Two Weapon Fighting, which is known to be subpar as Extra Attacks get into the game, since the benefits of +1 attack get diminished when you are already able to make 3 attacks anyway.

To summarize, the issue I have is:

• Two weapon fighting is already subpar.

• The feat that should make this style more viable is near useless.

The Proposal

With that in mind, I decided to change the Dual Wielder feat for something more in line with the glass canon damage dealer I have in mind.

Dual Wielder

Prerequisite: Two-weapon fighting (Fighting Style)

When you take the Attack action and attack exclusively with a light melee weapon that you’re holding in one hand (i.e., all attacks are made with the same light melee weapon, with the same hand), you can use a bonus action to take another Attack action in order to attack with a different light melee weapon that you’re holding in the other hand (again, all attacks should be made with the other weapon and other hand, respective to the previous attacks). If you do so, Attack Rolls against you have advantage until your next turn.

So, the idea here is that now, if you have Extra Attack, your bonus action actually can use them.

Comparisons

As baselines, I have used the following Pure Fighter builds:

• Greatsword, Great Weapon Fighting and +1 ASI.

• Greatsword, Great Weapon Fighting and Great Weapon Master.

• Two-weapon Fighting, +1 ASI.

After getting the feat, all levels are +ASI.

Obviously, at 4th level, TWF with +1 ASI is better (since you don't get extra attacks yet), as well as the GS+GWM. At 5th level, it is still worse than GS + ASI for all ACs.

At 6th level, it starts getting interesting as we get +ASI in our primary attribute and that is used in each of our attacks. However, GS + GWM still outdamages this feat for low ACS (AC <= 13), GS + ASI outdamages for high ACs (AC >= 19), and the feat is the best option for mid-range ACs (13 <= AC <= 19). Note that this still comes at the cost of being vulnerable to enemy attacks with advantage. An example figure for better visualization.

At 8th level, we get a +5 modifier in our main attribute and the feat starts to shine. It can only be outdamaged by GS + GWM for low ACs (<= 11), and shines for anything higher than that.

As we get higher proficiency bonuses and GWM starts to hit more often at higher ACs, GWM comes back against enemies up to 14 AC, however, the new feat still shines against high ACs - which are arguably more common at higher levels.

Trade-offs and concerns

So, basically, the feat gives a good damage potential (from my point-of-view), at the cost of being vulnerable. My concerns are:

• I can see this being quite overpowered for a Fighter 17/Barbarian 2, exploiting the Rage Damage for +2*8 extra damage and Reckless Attack basically giving advantage with no cost, as the enemies are already getting advantage in their attacks anyway. One way to solve this is simply not allowing both features to be used.

• I am not sure how this will impact Rangers with Hunter's Mark. Rangers are quite bad in 5e in my opinion, but this could be a game changer for them. Would they get too strong?

• Is simply giving advantage to attacks made from enemies enough to compensate for the considerable damage potential?

• On the other hand, is this as good as it seems? Are my baselines good baselines, or am I using subpar damage dealers anyway and outdamaging them is no big deal?

Additionally, there are a few trade-offs that are not obvious on how to evaluate and depend on the campaign:

• Getting one magic weapon is easier than getting two magic weapons.

• Forcing 8 Concentration saving throws is better than forcing 4 concentration saving throws.

• Having your bonus action for something else is better than not having your bonus action for something else (although it's hard for me to figure out what would be better than using it to considerably increase your damage).

So, for example, if we take into account a +3 Magic Weapon at 20th level, the GS + GWM build outdamages the new feat up to 20 AC, and loses by less than 10% above that, without costing the bonus action and without costing advantage for the enemies.

So, for now, I think this is decently balanced, but am I missing something? This is a very simple change and I would assume someone has already tried it out, if this is the case, I would love to get an answer from actually testing it.

In the case it is overpowered, is there some way to balance it through making it "cost" more, but maintaining the idea of attacking twice the number of usual attacks?

If it is underpowered... Well, then dual wielding seems to have no hope other than for flavor haha.

Answer 1

There are potential issues with certain ranger features

Your analysis convinces me that this feat is balanced against GWM for fighters. However, having played a TWF (revised) ranger from level 1-15 before ultimately respeccing, I see some potential issues there.

The most egregious example is the Gloom Stalker's Dread Ambusher feature. This grants an additional attack on the first turn of combat at level 3, which is already quite powerful. Your feat would allow a TWF Gloom Stalker to make 4 attacks on the first round at level 3 and 6 at level 5, which is too much. There are also a number of optimized "first round nova" builds that involve a three level Gloom Stalker dip, which all become even more powerful with your feat.

Your feat also creates problems for Horizon Walkers and Monster Slayers. Both sublcasses have level three features that allow them to use their bonus action for extra damage, either on a single attack or on one attack per turn against a single target. However, neither feature adds enough damage to be worth giving up two weapon attacks, so these features will be rendered obsolute for TWF rangers after level 5 (admittedly the Horizon Walker feature was already uncompetitive with a single offhand attack, but this makes it much worse). On the other hand, the Horizon Walker's 11th level feature will become considerably more powerful, allowing for 6 attacks per turn against 3 different enemies plus 60 total feet of teleportation. Overall, I don't think this feat would be unbalancing for either of these subclasses, but allowing a minor-moderate damage boost in exchange for rendering certain features useless will make them less fun to play.

Beyond specific subclass features, my frustration with the TWF ranger wasn't that I was too weak, it was that I had all these cool options for my bonus action but usually just wound up taking an offhand attack. You mention Hunter's Mark as a possible concern, and it's true that your feat would enable a lot of extra Hunter's Mark damage, but only if you are able to maintain concentration and attack the same target over multiple rounds. My experience was that I usually wound up needing to recast or move my Hunter's Mark every round or two, meaning it was almost never actually worth foregoing the offhand attack, and so an extra offhand attack would have meant I cast it even less frequently. Again, this probably isn't badly unbalancing, but it would make a character that I already found frustrating to play even more so.

Based on my experience, the way to make TWF more fun and more viable for rangers is to allow a single extra weapon attack without using a bonus action, rather than allowing multiple extra attacks as part of the bonus action. I don't know exactly how to balance this as a feat or fighting style, but that's the direction I would explore.

There are potential issues with other classes

Requiring the TWF Fighting Style means that this feat will mostly just be taken by figthers and rangers (and swords bards, I guess), but it's also worth considering other class features that may interact with this feat, most likely through multiclassing. I'm less confident that these will be big issues than the ones I raised above, but you should still keep them in mind.

• As you noted, this feat synergizes well with rage and reckless attack on barbarian/fighter multiclass characters.
• Paladin/fighter multiclass characters with this feat will be able to use Divine Smite four times per turn, and benefit from 4 Improved Divine Smite dice at level 12.
• An artificer or their friend could dual-wield throwing weapons infused with Returning Weapon and make 4 ranged attacks per turn.
• Martials that don't rely on Extra Attack (eg rogues) will get no benefit from this feat, so I would recommend including it as an addition rather than a replacement of the original.

Lots of attacks means slower combat

This isn't a balance consideration, but worth bearing in mind. A level 11 TWF fighter will make 6 attacks per turn, or 9 with Action Surge. I am currently playing a Gloom Stalker/Fighter multiclass which can make 6-7 attacks on just the first turn, and I find that takes a long time to play out. If I were doing it every turn I think it would become frustrating for everyone else at the table.

TL;DR: If this feat is intended to support a player who wants to build a dual-wielding fighter, it's probably okay although it may slow down combat. But if this is intended to replace the original for any and all TWF builds, it may still need work

Answer 2

As written it won't terribly unbalance your game

with the exception of the Barbarian Reckless Attack exploit that you noted and for Gloomstalkers as mentioned by Joe. It is a damage boost and it can make but generally it remains within regular limits.

With regards to damage output it appears to stay just above the expected damage of GWM for ACs 14+ with the greatest gains at lower levels and higher ACs. Against AC 20 at level 20 it does 20% more damage whereas against AC 14 it does 0.4% more damage. Against AC 13 it ranges from 1% worse at very low and very high levels and up to 5% better during middle levels. Overall the damage ranges from marginally worse to significantly better. If I only cared about maximizing average damage I would probably be best served by your Dual Wielder feature over GWM. Your improvement directly helps Fighters the most because of all of the additional attacks. For Rangers it creates benefits with the Extra Attack and with Hunter's Mark. This gives Rangers a more significant boost from the style below level 11 but creates some different issues discussed below.

Regarding Hunters Mark: Your feat boosts the potential damage of Hunters Mark but it also creates increased risk of concentration checks. It takes a round to set up since the bonus actions conflict so you will have at least 1 round when enemies can target you before you can use the extra attacks.
Round 1: Draw sword, cast Hunters Mark, Attack
Round 2: Draw 2nd sword, Use Dual Wielder, Attack * 2
Before level 5 this gives potentially 3d6 damage if the ranger keeps concentration. After reaching level 5 this increases to 6d6.
Alternatively
Round 1: Cast Hunter's Mark, Attack with bow, stow bow
Round 2: Draw Sword, Attack
Round 3: Draw 2nd sword, Use Dual Wielder, Attack x 2

At higher levels, Hunter's Mark also becomes a less useful usage of concentration. Since attack against you have advantage and monsters generally have multi-attack it will be much harder to use Hunter's Mark effectively.

I recommend including the "You can draw or stow two one-handed weapons when you would normally be able to draw or stow only one" aspect of the original because it makes dual wielding less finicky and lets players feel stylish. This will, however, boost the utility of Hunter's mark.

Some things to consider about the damage that you didn't mention:

• Multiple attacks can target multiple enemies. Unlike with GWM you will be able to essentially split the damage between targets if the first one dies.
• Consistent damage is better than volatile damage. GWM increases the overall miss chance so even though average DPR is boosted there will be a lot more attacks of 0 damage. This is mitigated by extra attacks but it does increase the chances that some bad luck will cause you to lose the fight. It also makes resource planning more difficult because caster might not know whether a fight will be easy or hard (and so whether it is the right time for a higher level spell) because the dice have greater weight.

I would recommend using a static penalty of -4 or -5 to AC rather than advantage on being hit. -5 to AC tends to be marginally worse than advantage to be hit (with AC 17 at most 4% worse with a +9 hit bonus). This solves the issue of the Barbarian multiclass and creates additional risk if the enemies already have advantage.

An alternative to your suggested feat is to instead replace the Two Weapon Fighting style. The style grants a major bonus to damage before level 5 but swiftly becomes worse than Great Weapon Fighting style. I would recommend the following:

Two Weapon Fighting Style
Every time you attack with a melee weapon you are holding in one hand as part of an Attack Action can make an additional attack with a melee weapon that you’re holding in your other hand. Doing so consumes your bonus action for the turn. You don’t add your ability modifier to the damage of the additional attack, unless that modifier is negative.

If you can't add your damage modifier to the additional attacks then the average damage output is only .67 more per attack than using Great Weapon Fighting. You get the ability to hit more enemies (better split damage) and get more reliable damage because you will do 0 damage less often but you will still have worse opportunity attacks and readied actions. This also removes the low level advantage of dual wielding. This still synergizes terribly well with Hunters Mark but it takes a round before you can use both. The Gloom Stalker does break this but this can be solved by making the Gloom stalker's extra attack on the first round of combat independent from the Attack Action. This is a minor buff but likely will not change anything because Gloom Stalkers are already likely to Attack on the first round regardless.

If you want a feat for dual wielders you could then have the feat give the ability add your attack modifier to the additional attacks for a -4 to AC. Since this is about a +5 per attack it is similar in average output to GWM including the reduced chance to hit. The reduction in AC balances out the advantages of being able to split the damage and having more reliable damage.

This would read something like this:

Dual Wielder
When you engage in two-weapon fighting your weapons do not need to be light. You can also add your ability modifier to the damage of attacks with your offhand weapon.

This also gives a benefit for rogues but they also will frequently be tempted to disengage/dodge if they hit with the first attack so the benefit will be less frequent. At higher levels the benefit will become negligible because it won't scale.