Barbarian with Dual Wielder feat and shield

Question

Just as a clarification to Would dual wielding a sword and shield as an improvised weapon count for dual wielding perks?:

If I have the Dual Wielder feat and Extra Attack (level 5 Barbarian) and I'm wielding an axe and a shield, can I attack 4 times during my Attack action (axe, shield, axe, shield)? And does each of those attacks deal bonus damage from rage? And do I get the +1 AC from Dual Wielder feat because the shield is considered an (improvised) melee weapon (while I still get +2 AC from the shield itself)?

Answer 1

No, and Yes.

First of we need to consider this post by Jeremy Crawford:

Dual Wielder is intended to work with actual weapons. Using the feat with improvised weapons is up to the DM.

See also: Shield and Improvised Weapon

It is not RAI to use a shield or other improvised weapon with the Dual Wielder feat. The rest that follows assumes you talked your DM into allowing that.

One Bonus Action

can I attack 4x in my Attack action (axe, shield, axe, shield)?

You can attack twice in your attack action, after level 5.

You, however, only get one bonus action to make one more attack if you attack with a light weapon you could attack (axe, axe, Shield), if your DM allows you to attack with the shield.

Relevant text from PHB 195:

you can use a bonus action to attack with a different light melee weapon that you're holding in the other hand.

So, you get a total of 3 attacks.

Rage Bonus Does Apply

Rage is a modifier added to the damage, so the following rule (also PHB195 would apply):

You don't add your ability modifier to the damage of the bonus attack, unless that modifier is negative.

Rage, however, is not an ability modifier, and still would apply. You wouldn't, however, add your strength modifier without the feat -- but since we're talking about with the feat your good on this front.

+3 to AC — Um... Maybe?

I'd argue it is either a shield or a weapon depending on how you are using it. I, personally, don't think a shield grants any more armor because it is being used a weapon. That said, using the shield is already against RAI, but might be allowed, and if the DM allows that, you could push for the +3 -- but I think it is a stretch.

Answer 2

First and foremost we need to understand the RAW versus RAI for Improvised Weapons and how they interact with any other feat other than Tavern Brawler.

For that we can look here for a better understanding of the intention. You can use a shield or some other object as an improvised weapon to make a (melee or ranged) weapon attack; but turning some other object into a temporary weapon does not magically grant it the statistics of a weapon (such as a light, thrown, 1d4 Dagger you could dual wield; or a versatile 1d8/1d10 longsword).

What this means is while an improvised weapon might make the DM have to look up what the closest relevant weapon might be, it is never in fact that weapon and does not count as that weapon. Your shield is always only ever a shield. While I might personally rule that if you use a shield you are wearing in a way as to grant you AC +2 as an improvised weapon, you are no longer wearing it in a way it could grant you +2 AC; I have no rules to back this up with.

So with all that being said;

You get 3 attacks, not 4

if you had the Dual Wielder Feat plus Extra Attack with Rage and you are wielding an Axe and another 1 handed non improvised weapon that fulfills the requirements for the Duel Wielder feat (Or an improvised shield weapon as per your DM's approval) ; you would get 3 attacks, not 4. No matter how many Extra Attacks you can take, you may only take 1 bonus action per turn, and Two Weapon Fighting forces you to use a bonus action to swing with your offhand weapon. So your attack would look like: Attack Action Axe, (Bonus action off hand during either two attacks), Extra Attack Axe.

Yes, Bonus Rage damage applies to all weapon attacks.

Unless your Barbarian had the Two-Weapon Fighting Fighting Style, he is not allowed to add his ability modifier to the damage of the offhand weapon; luckily rage is a Class Feature that provides a flat bonus, not a bonus that comes from an ability modifier.

Lastly, you would gain the +1 bonus from Dual Wielder, but if you kept the +2 bonus from using your shield as a shield would be up to your DM just like allowing the improvised weapon to count as a legal weapon for Feat interactions, since you are using it as a weapon in this instance and not a shield that could grant you +2 AC.

Answer 3

I use an alternative ruling: In my game, you can't use worn items as improvised weapons.

If you want to hit someone with a worn item (bash them with a shield, punch them with a gauntlet, kick them with a boot, head-butt them with a helmet, elbow-strike them with a greave, and so on) then it comes under the unarmed attack rules, not the improvised weapon rules.

I find this ruling keeps things simple. In the past, I've seen players go from "a shield is a weapon, so I get 2WF bonuses" to "gauntlets are a weapon, so I get 2WF bonuses" to "gloves are a weapon, so I get 2WF bonuses".