Number crunchers needed for homebrew feat.

[Keltest]

Pretty much what the title says. I've got a new campaign coming up soon ish, and I'm planning on introducing some homebrew feats. Specifically in this case one to compete with sharpshooter and great weapon master. However, I am bad at math, and am unsure how well it would compare.

Specifically, my planned feat would allow you to, if you are wielding a one handed weapon in each hand, to take a -5 penalty to hit in order to make an extra attack with each of your main hand and off hand weapon.

What I would like to know is, how does this compare on DPR against sharpshooter or GWM? I assume that as attacks per turn increases it falls behind due to lack of scaling, but at 1 or 2 attacks from the attack action, can it keep up? Furthermore, is the attack penalty too high, given that it adds additional attacks rather than flat damage? I'm considering making it a -2 or -3 penalty instead, so the damage doesn't suffer so much from missed attacks in the long term.

So to any math inclined members, can you help a DM out?

[PhantomSoul]

It will depend a lot on what those attacks are -- does the attacker have per-hit bonuses to stack up and are they flat bonuses or dice? Per-round bonuses to stack up and are they flat bonuses or dice? On-crit bonuses? It'll also depend on the required attack roll (so target AC vs. attack bonus), advantage vs. disadvantage vs. neither (and if advantage is elven accuracy), etc. How do you want it to apply for a rogue (one base attack) vs. a fighter (up to four base attacks)?

Overall, though, I'd be hesitant to give lots of extra attacks, but for it being two-weapon fighting it could be feasible to do something like that. I'd tend to want it to be a -2, a -5 or a -1d4 (or other die), just because those are more common in the system.

[Kane0]

I’m not the most accomplished math guy here but sure, can take a look for you

[Keltest]

It will depend a lot on what those attacks are -- does the attacker have per-hit bonuses to stack up and are they flat bonuses or dice? Per-round bonuses to stack up and are they flat bonuses or dice? On-crit bonuses? It'll also depend on the required attack roll (so target AC vs. attack bonus), advantage vs. disadvantage vs. neither (and if advantage is elven accuracy), etc. How do you want it to apply for a rogue (one base attack) vs. a fighter (up to four base attacks)?

Overall, though, I'd be hesitant to give lots of extra attacks, but for it being two-weapon fighting it could be feasible to do something like that. I'd tend to want it to be a -2, a -5 or a -1d4 (or other die), just because those are more common in the system.

In general, I'm not too worried about edge cases. I don't have any crit fishers or dexadin elf dual wielders, and the only fighter is using a 2h sword because his player likes big dumb weapons. Specifically, I have a barbarian who will be dual wielding, and I don't want him to feel like his damage is super low compared to the fighter. I don't need it to be an equivalent, just to feel meaningful in comparison.

[Senjou]

I would say instead it is quite op. When you increase the flat damage with GWM you are trading one miss for a increase in damage. In the long run they kinda average out unless you have lots of way to increase atk bonus. In your case the opportunity cost is gone. You are just increasing the damage by a flat number which can be calculate as (wmdg)*(%hit) where %hit is equal to ((21-5-AC+AB)/20) (without advantage), Hit% (Advantage) = Hit% + (1-Hit%)*Hit%, Hit% (Disadvantage) = Hit%^2 (thanks LudicSavant for the formulas . Even in the worst case scenario, always disadvantage, the increase in damage (considering enemy AC 13 for 1 level enemy but it scales with the game), Dex 16 and two shortsword (1d6+3) it would result in an average increase of 2.6 per attack (so 5.2 in totale) without opportunity costs. And this scales with level and magic weapons hard, really hard.

tldr too op because there is no opportunity cost like in gwm

[Keltest]

I would say instead it is quite op. When you increase the flat damage with GWM you are trading one miss for a increase in damage. In the long run they kinda average out unless you have lots of way to increase atk bonus. In your case the opportunity cost is gone. You are just increasing the damage by a flat number which can be calculate as (wmdg)*(%hit) where %hit is equal to ((21-5-AC+AB)/20) (without advantage), Hit% (Advantage) = Hit% + (1-Hit%)*Hit%, Hit% (Disadvantage) = Hit%^2 (thanks LudicSavant for the formulas . Even in the worst case scenario, always disadvantage, the increase in damage (considering enemy AC 13 for 1 level enemy but it scales with the game), Dex 16 and two shortsword (1d6+3) it would result in an average increase of 2.6 per attack (so 5.2 in totale) without opportunity costs. And this scales with level and magic weapons hard, really hard.

tldr too op because there is no opportunity cost like in gwm

There is an accuracy penalty in my feat as well. More swings for less accuracy. My concern, and thus the need for math, is whether a -5 penalty with this many hits is going to adversely affect the damage over time too much.

[Senjou]

The -5 is taken in account in the to hit calculation. You have not specified if this replaces one of your attack or if it is a bonus action

[Keltest]

The -5 is taken in account in the to hit calculation. You have not specified if this replaces one of your attack or if it is a bonus action

It's when you take the attack action, the same as GWM and SS. The penalty applies to all attacks taken that turn, not just the two extra attacks from the feat.

[Man_Over_Game]

Assuming I understand it correctly, you take a -5 to two of your attacks to make another round of those attacks.

So you're basically doubling your damage by taking a -5 to hit. So this means that the -5 cannot cut your damage in half. So as long as you need less than a 10 to hit normally, you're gaining profit. Not by much, tho.

[Kane0]

Could I grab the proposed feat in its entirety? Easy for me to slot into a previous numberchart i've run up that way.

[Keltest]

Could I grab the proposed feat in its entirety? Easy for me to slot into a previous numberchart i've run up that way.

MOG summed it up pretty well a couple posts ago. Wording to be worked on as is convenient for me, but the intent is that you can take a -5 penalty to hit for all attacks this turn in exchange for an extra attack from each weapon. So 4 attacks total, with the bonus action off hand strike and no extra attack feature.

My assumption is that it will scale stronger than GWM for styles that have a per hit damage bonus, and weaker for ones that get extra attacks. But I don't want to assume, hence some math being needed.

I'm on mobile right now, so if you need something more formal it might have to wait a couple hours.

[Man_Over_Game]

Yeesh, that's expensive. Even on a 1:1 ratio, you're still looking at a situation where you'd want to need no more than like 7 to hit to make it worthwhile. On top of it just being bad if you have Extra Attack, I'd probably rethink the feat. I get that you're wanting to avoid stacking too much benefit with on-hit effects, but it'll be a bit of a stretch if you think you're going to outpace a Warlock in terms of cost and power so easily.

And anything weaker than the best possible option is balanced.

[Keltest]

Yeesh, that's expensive. Even on a 1:1 ratio, you're still looking at a situation where you'd want to need no more than like 7 to hit to make it worthwhile. On top of it just being bad if you have Extra Attack, I'd probably rethink the feat. I get that you're wanting to avoid stacking too much benefit with on-hit effects, but it'll be a bit of a stretch if you think you're going to outpace a Warlock in terms of cost and power so easily.

And anything weaker than the best possible option is balanced.
Yeah, that's what I was afraid of. Would lowering the attack penalty a couple points improve it to more tolerable levels, or should I just use a different trade off? If I need a different one, do you have any thoughts on what it should be?

[Kane0]

Okay so a bit rough but here is what I got (You can ignore column E)

Notes:
X + Y attacks means X number of attacks using your Action and Y number of attacks using your Bonus action over the course of the three rounds.
I let Pally use Two-Wep style, because why not
GW style is calculated as +1 damage for simplicity
Zweihander column uses PAM for the feat, not GWM
The -5 to hit being a 25% reduction in damage output probably isn't entirely indicative of its real effect
Crits aren't taken into account


I'll let you draw your own conclusions, but doesn't seem wildly out of balance on first glance. It reminds me of the Samurai ability, trading a significantly boosted number of attacks at the cost of the chance of them landing. In fact, this could get a little silly if you put the two together.

https://i.imgur.com/KtJxAp4.jpg

[Man_Over_Game]

GWM or SS, without Advantage, gives about a +2 damage bonus in an average situation (with like an 8 on-the-die to hit normally). That doubles with Advantage.

Also keep in mind that this isn't accounting for the bonus effects those feats grant.

Assuming you're playing a normal class, you're looking at about +4 damage per round without an additional investment, and +8 damage per round with additional investment (Advantage).

Now, GWM and SS generally get Advantage from somewhere as the form of investment, but you could use the same logic to apply for any on-hit effects (which, I should stress, should not be necessary to gain value from this feat).

Assuming the average roll that a player needs to hit with default rules is always about an 8, a -3 to hit totals for 75% damage with your normal attacks, for a final result of 150% total damage. Which I'd say is perfectly fine, considering this feat comes with additional cost (your Bonus Action, doesn't work out-of-round) and most on-hit effects are initiated with your Bonus Action (meaning you're almost never using this feat in the first round of combat).

With Extra Attack, I think this would drop down to 112.5%, which I'd debate is not worth a feat but it's hard to say. Just a reminder, this is with a -3 to hit on all attacks that turn.