Since April's sub was a fighter, now's a good time to dig into fighter math! I know I did this for monks last month — don't worry, math haters, this won't be an every-month theme.

As with other subs, I chart out fighter damage in a big ol' spreadsheet, where I've got WotC's fighters diagrammed against mine. The sheet's not perfect, but it helps to establish baseline damage numbers and give me a sense for how strong a sub's likely to be. (Math comes first; playtesting after).

I'm going to be making a bunch of references to last month's monk post, so if you haven't read that yet, you might want to.

Simplifying Assumptions

Let's review the same assumptions I made for the monk chart.

Every combat lasts 3 rounds.

This is a pretty standard simplifying assumption; I forget if it comes out of the DMG or somewhere, but ~everybody has used this one forever.

Every day has 4 combats.

This is maybe a little controversial, but I find it works well. The official guideline is 6-8 encounters per day, but that's always been laughably high; it's only mechanically achievable if lots of them are easy, and only narratively achievable during a dungeon crawl. A lot more of the DMs I know do something more like 2-6 encounters, with the combats skewing to the Hard/Deadly ranges.

Every day has 1 short rest.

While the "ideal" adventuring day always includes 2, there are lots of tables where this is uncommon. We'll touch on this a bit more later, though.

More Assumptions

A few more things we'll stipulate for the sake of fighters.

Action Surge isn't real.

This is imperfect but so helpful. Modeling action surge is a moderately big pain in the ass. In the simplest case, you'd just multiply a fighter's damage by 4/3 (because they take 4 actions in the time another class would take 3). But that works poorly for any sub that's heavily dependent on bonus actions, and produces big disparities for Polearm Master or Crossbow Expert builds.

But! We're only comparing fighters here. They all get Action Surge, so let's just say "they all get pretty good value out of it" and move on.

Fighters start with a 16 in their key stat, get it to 18 at level 4, and 20 at level 6. They start picking up the big combat feats at level 8.

I didn't talk about the big combat feats in the Monk post since monks struggle to use them. We'll go into more detail later.

Sword-and-board or spear-and-board (Polearm master) builds always take the Dueling fighting style. Ranged builds always take Archery (but we'll tend to ignore them; they're giving up on the fighter's useful ability to hold down a front line). Everybody else always takes the Defense style, so we don't have to model them. (The Great Weapon Fighting style never even gets to +1 damage per attack; it's generally not worth taking).

Set the Baseline

Aaaand it's already looking a little tricky. The Champion is the only fighter sub in the SRD, and very much the default fighter sub, and it...sucks. It gets Improved Critical at level 3, which is weak. Level 7's not an offensive feature. Level 10 is a second fighting style: in rare cases you might grab an offensive choice so you can switch between two cool weapons, but 90% of the time you'll just pick up Defense for an extra +1 to your AC. At level 15 the crit range expands again. And the level 18 feature is actually great combat regen, but not something we care about for a damage model.

To start off my damage chart, I have a Baseline fighter (with no subclass), doing the most basic build possible: sword and shield, no combat feats. The Champion sits right next to it, doing...slightly more damage. Seriously, check this out.

The biggest difference, at level 20, is 5%. That's nothing. If I want a good reference subclass to balance around, the Champion ain't gonna be it. Mathematically, the reason for that is just that critical hits are not a meaningful contribution to damage. If you only have a 5%, or 10%, or even 15% chance to crit, then you weight a crit's damage by that number. A greatsword crit is 7 bonus damage, and 15% of 7 is a whopping 1 point of damage.

So if the champion's a bad baseline, what's better? In steps the Revised Champion.

KibblesTasty's Champion

I know Kibbles, and I trust his work, and I know specifically that his Champion revision has been playtested to hell and back. It buffs Improved Critical to scale faster, buffs all the fighting styles, and does some other stuff that doesn't matter for a damage model. So let's chart it out and see how it compares.

That's another featless sword-and-board on the left, and the dreaded GWM+PAM on the right. Our featless build is comparing well to the baseline fighter now, generally doing 10-15% more damage. That feels more like what a fighter sub ought to be.

Let's Talk Feats

Okay, rather than run through the charts for every single subclass, let's do a big detour to talk about combat feats. Generally in 5E, most fighters and half-casters want to pay attention to one or more of the big four combat feats: Crossbow Expert, Great Weapon Master, Polearm Master, and Sharpshooter. Two of those (CBE and PAM) enable you to make an extra attack as a bonus action; two (GWM and SS) let you power attack, sacrificing -5 to hit for +10 bonus damage. Generally, any fighter (and many half-caster) is going to want to grab one of these in tier 2 to make sure their damage scales well into the late game.

When we went over the monk charts, we could ignore these; monks already have plenty of uses for their bonus action, and they (almost) never use greatweapons or ranged weapons. It's a different story for fighters. I think it's useful to produce a "baseline" build for every subclass that doesn't rely on the big combat feats, and then a "moderately optimized" build that picks up one of the four. (You can also do a "heavily optimized" build that picks up two, either CBE+SS or GWM+PAM. I don't usually bother to chart them, but I will use that Champion GWM+PAM above as an upper bound on where damage numbers can go.)

We'll use this sword-and-board as our baseline build and this GWM+PAM as our topline.

Back to WotC's Fighters

Okay, with the Champion out of the way, and replaced as our baseline with the Revised Champion, how do the rest of WotC's fighters come out? They're all kind of a pain.

Battlemaster

The Battlemaster is the single hardest thing to model in this whole sheet. This is because it gets 23 different maneuvers it can use; it ultimately learns 9 of the 23. I'm not going to model all of those combinations, because they don't make spreadsheets big enough. But I'll do two very powerful and popular setups.

First: the degenerate (ri)poster. Riposte lets the Battlemaster make a retaliation attack when an enemy misses it in melee; in a completely extreme example, let's assume we manage to spend every single superiority die on Ripostes.

Second (and more realistic): the GWM expert. This is a Battlemaster that uses Feinting Attack (spend a bonus action to get advantage on one attack) or Tripping Attack (knock an enemy down when you attack, to get advantage on all subsequent attacks) at every possible opportunity. And anytime it has advantage, it activates GWM for a +10 damage boost. This build is knowingly going to chart high because I'm not modeling the chance that the enemy makes its save and Tripping Attack fails (that way lies madness).

Eldritch Knight

EKs are another one where the math immediately gets gnarly and the build paths get branchy. There are three big considerations we have to make. First off, 5E or 5.5E? Easy enough — I write for 5E, so we'll balance around that. Second, do you allow the SCAGtrips? These are Booming Blade and Green-Flame Blade, the two cantrips from the Sword Coast Adventurer's Guide (hence "SCAGtrip") that make a weapon attack and then add more effects on top of it. I personally ban them; they're not gamebreaking on their own but it's easy for them to get there. Third, does the EK have to use a spell focus? That one's a very bitty mechanical question, but sword-and-board EKs are very popular (because they can get bonkers-good AC); strict rules-as-written, though, they can't cast spells with their hands full unless they take the War Mage feat.

So we'll have three variant builds here:

Sword-and-board that handwaves the spell focus rule, probably the most popular build before SCAG came out. We'll give it Poison Spray to maximize theoretical damage, though I think Fire Bolt is surely more popular and Frostbite is I suspect secretly the best choice.

Sword-and-board with Booming Blade as its cantrip of choice, which manages to trigger all the bonus damage every time. Most 5E tables do allow the SCAGtrips, which means this is a very popular build.

Greatweapon build with Booming Blade as its cantrip of choice. This is technically the only build of the three that's legal, because thee fighter can take a hand off their sword to reach for a component pouch.

The Rest of WotC

Those are the hardest ones to model for sure. As for the rest:

Arcane Archer was a little tricky but presents a single clear build path (Sharpshooter).

Samurai's pretty easy (it likes a GWM or SS build equally, since Fighting Spirit gives it tons of free advantage).

Echo Knight has a wide-open build path, but mildly prefers to be in melee; it also doesn't get much bonus damage.

Rune Knight has an optimal damage build if you focus on the Fire Rune, but that's actually not its optimal build overall; it excels as a grappler. Still, we can model the damage build.

Psi Warrior works out really strong because its psi dice are so plentiful; in practice it can use a psi die almost every turn, and by tier 3 multiple times per turn.

Lessons

The monk deep-dive showed us a clear change in WotC's design ethos: older monk subclasses were designed around using Flurry of Blows as their primary damage tool, while newer monk subs got alternatives to it. Fighters have no such consistency. Instead, their mathematical balance circles around how they can best use the big damage feats. I don't know if that's intentional on WotC's part or just a design artifact: of course the class that makes the most attacks cares the most about feats with every-attack effects. Even before you get to tier 3 and 3-hit Extra Attack, Action Surge already gives you ~30% more attacks than everyone else.

The practical upshot of this is that designing a fighter sub requires engaging with the big combat feats (but also, not! because there are still tables that don't use feats, and players that will pass them up for something more interesting instead). I'm going to avoid posting a chart, then; the monk chart was hard enough to read, and this one's got twice as many lines, since I've got feated and featless builds for every sub.