Unintended Consequences of Merging Constitution into Strength

[zergling.exe]

I'm putting some houserules together to try and make all ability scores useful, however I'm having a hard time trying to get Str to be useful to casters. Then I had the thought of combining Con and Str into one stat. What unintended consequences would this have apart from making larger creatures even more durable and smaller creatures even more fragile? Undead and Constructs would either lose their bonus HP from whatever source or get to have bonus HP from a high Str score and have their HD size reduced (at least for undead).

Anything else I should be aware of before implementing this change?

edit: Plenty of views, so I'll add some context for my group. They play core only (previous DM owns PHB, DMG, and MM1 from family) and I don't feel like it'd be worthwhile to try and change that. They are also fairly low OP and like 4Es maneuvers but dislike ToB. How I'm not entirely sure.

These are the changes I already have for the ability scores:
Str: All weapon damage
Dex: All to-hit
Wis: Initiative
Cha: Will saves

Anything unlisted is the same as before.

[Castilonium]

Two things I can think of. Finesse melee characters would be even squishier than their strength based, full plate wearing counterparts. Also, how would you change point buy?

[Florian]

Two things I can think of

Let's add a 3rd and 4th: Barbarians should know how "death by rage" works. Rejoice, martial classes, when your Bull´s Strength runs out, you will know that fine experience, too! Going from there, STR or DEX damage/drain is annoying but doesn't kill you - Con does.

Beyond that, it´s easy enough to run D&D with two stats: Might and Magic.

[weckar]

You are rolling together two of the already strongest stats into one. Both already have multiple common uses. STR has melee accuracy (touch attacks too!), carrying capacity and those important athletic skills. CON meanwhile mainly governs health and fortitude saves. I am not sure why these are your candidates while the simple CHA only helps some skills and... not really much else.

[Malroth]

add in the blood magic spell from Pathfinder and every caster will take Str for their secondary stat if not their primary. You'll probably see a lot more Anima mages or Meldshaper dips.

[weckar]

Hellfire Glaivelocks will also have a field day with this.

[Fizban]

Since merging stats is already effectively a buff, maybe try more buffs: give dex damage bonus to match strength (either on ranged weapons, ranged and finessable weapons, or even just all weapons with 1.5x on finessable weapons) and let people use either dex or con for hit points. Now the choice is between bigger weapons, heavier armor, and fort saves, or lighter weapons, lighter armor, and reflex saves. It's basically just two versions of "might" in the might and magic setup (good reference), but that's what people seem to want from the ability score system anyway.

[Eldariel]

Not your precise question, but my own preferred solution is to keep them separate, and key natural movement speed off Str. Movement is quite useful to casters as they tend to be free to take move actions a lot, and it makes perfect sense too; how fast you can go is all about how strong you are. How long you can maintain that is a matter of constitution, of course, and how accurate turns, movements, etc. is dexterity but the raw numbers should fall under Strength.

It's worth noting that Constitution is already a big stat for basically everyone; making it even more powerful may skew character creation even further. Combining Con and Str would also mean basically everyone is a powerful melee combatant on low levels. Before class abilities kick in, attacking is mostly a stat check and since casters want Con secondary anyways, they'd be able to do just as much with combat maneuvers and melee combat as non-casters on low levels.

You are rolling together two of the already strongest stats into one. Both already have multiple common uses. STR has melee accuracy (touch attacks too!), carrying capacity and those important athletic skills. CON meanwhile mainly governs health and fortitude saves. I am not sure why these are your candidates while the simple CHA only helps some skills and... not really much else.

Str is quite weak for casters. Athletic skills are completely irrelevant for someone who often uses magic to move (Fly alone tends to negate them all aside from perhaps Swim for which you have Freedom of Movement or equivalents, not to mention Teleport), melee touch attacks are generally frowned upon in general unless you use a way to make them ranged (being next to things who want to hit you in the head is usually not optimal, particularly with AoOs and Mage Slayer and company in the game) and carrying capacity is generally only relevant to those wearing armor - and even then, extraplanar spaces negate it. It is certainly the weakest stat in the game.

Dex and Con are obviously immensely useful, casting stat is just everything to a caster, Wis has Will-saves and some common general skills (most saliently Perception/Spot and Sense Motive, which are the "defensive" skills, as well as defending against Intimidate and some abilities like Ragewalker's Frenzy), Cha is used for some spells (Charm Person-line, Planar Binding-line, all spells that can have contests of control at least) and Cha-skills are much more powerful than Str-skills (Use Magic Device) and Int is of course a god tier skill due to the dearth of skill points and the power of particularly Int-based skills (Spellcraft, Knowledges, Search, etc.) in the system.

[ayvango]

Two things I can think of. Finesse melee characters would be even squishier than their strength based, full plate wearing counterparts.

Made Finesse add dexterity to damage if you use dexterity to attack. In that case it would be reasonable to max both ConStr for Dex for double damage with light weapons.

[Fizban]

Strength is already tied to movement speed, in theory. People with 10 str only have a 33lb light load capacity, if you're actually trying to carry anything more than the clothes on your back and a day's worth of rations those 30 lbs get filled up real fast. Even 14 str only raises that to 58 lbs. The problems are multiple of course, since people can just choose to not bother with the 6lb light crossbow and 3lb/10 bolts they'd be expected to carry, assume their pack mule never gets hurt, and magical storage is cheap and assumed to be easily available. Run out their low level spells with mooks, eat the donkey, and ban Handy Haversacks, and low-str characters will be taking that speed penalty even in light or no armor.

That's in opposition to heavy armor of course. It takes a lot of dex to get high enough you can downgrade from chain shirt to get more capacity that way, but medium and heavy armor just disqualifies you up front.

[Anthrowhale]

An AeshKrau Illumian can get many extra spell slots from strength.

Leaving aside (greater) consumptive field but using persistent spell, there is Giant size(+32), Spider Curse (+4), Righteous Might (+8 Size), Infernal Transformation (+4 Profane), Holy Transformation (+4 Sacred), Bite of the Werebear (+16 enhancement), and Aura of Vitality (+4 Morale). Altogether, this gives about 9 extra spells / level with an Archivist potentially able to fully leverage all spells.

[weckar]

Str is quite weak for casters. Athletic skills are completely irrelevant for someone who often uses magic to move (Fly alone tends to negate them all aside from perhaps Swim for which you have Freedom of Movement or equivalents, not to mention Teleport), melee touch attacks are generally frowned upon in general unless you use a way to make them ranged (being next to things who want to hit you in the head is usually not optimal, particularly with AoOs and Mage Slayer and company in the game) and carrying capacity is generally only relevant to those wearing armor - and even then, extraplanar spaces negate it. It is certainly the weakest stat in the game.

I agree, but if you roll em into one, you can't just do it for the casters.

[Eldariel]

Strength is already tied to movement speed, in theory. People with 10 str only have a 33lb light load capacity, if you're actually trying to carry anything more than the clothes on your back and a day's worth of rations those 30 lbs get filled up real fast. Even 14 str only raises that to 58 lbs. The problems are multiple of course, since people can just choose to not bother with the 6lb light crossbow and 3lb/10 bolts they'd be expected to carry, assume their pack mule never gets hurt, and magical storage is cheap and assumed to be easily available. Run out their low level spells with mooks, eat the donkey, and ban Handy Haversacks, and low-str characters will be taking that speed penalty even in light or no armor.

Only loosely. It helps avoid penalties but it doesn't grant a bonus. 6000000000000000000000000 Str creature moves just as fast as a 1 Str creature provided both are unencumbered. And you really don't need that much in terms of items in this game. All spell components weigh more or less nothing and items of actual relevance the same. Casters don't need weapons (though a ranged weapon and an execution weapon are nice in certain cases but they're certainly luxury items rather than musts) and spells tend to outperform all the mundane items in terms of utility, even lowly cantrips. Ratios, gold, and the like are really heavy so you should either outsource them, get a Ring of Sustenance, or solve it through some other means. Note, you can also just carry a backpack with stuff and drop it for combat to gain full movement for the duration of fights. You'd think that would open you up to theft but frankly, it's almost as easy to steal stuff off someone's person as from the ground (getting nearby unnoticed is the tricky part, the Sleight of Hand DC is quite low).

I agree, but if you roll em into one, you can't just do it for the casters.

Warriors benefitting more of their native stats is really probably just fine though. You'd expect the guy who trains all his life to both, hit harder and be more durable than the guy who has never run 1 metre. And run faster for that matter, hence my earlier point.

Of course, yeah, buffing strength is way too easy for casters as long as Polymorph exists so it doesn't really solve much except incentivise them even more to use those spells so meh. But if you go with e.g. PF Polymorph, it already gets a lot better.

[zergling.exe]

Plenty of views, so I'll add some context for my group. They play core only (previous DM owns PHB, DMG, and MM1 from family) and I don't feel like it'd be worthwhile to try and change that. They are also fairly low OP and like 4Es maneuvers but dislike ToB. How I'm not entirely sure.

These are the changes I already have for the ability scores:
Str: All weapon damage
Dex: All to-hit
Wis: Initiative
Cha: Will saves

Anything unlisted is the same as before.

Two things I can think of. Finesse melee characters would be even squishier than their strength based, full plate wearing counterparts. Also, how would you change point buy?

My group likes to roll, so point buy is a non-issue.

Let's add a 3rd and 4th: Barbarians should know how "death by rage" works. Rejoice, martial classes, when your Bull´s Strength runs out, you will know that fine experience, too! Going from there, STR or DEX damage/drain is annoying but doesn't kill you - Con does.

Beyond that, it´s easy enough to run D&D with two stats: Might and Magic.

Everyone already has to worry about that with Bear's Endurance, so I don't see why that adds a new thing.

[Vaern]

The importance of strength to casters is in the form of carrying capacity and comes in mid to late game, especially for clerics and bards as their ability to wear armor tends to weigh them down more than sorcerers and wizards. Especially if the bard is stereotypically a gnome, as small creatures have inherently reduced carrying capacity. My bard's equipment, without miscellaneous odds and ends, keeps him within just a couple pounds of his light load limit. More than anyone else in the group, I need to pay careful attention to what I pick up to keep myself from taking weight penalties.

[Castilonium]

small creatures have inherently reduced carrying capacity.

Funny foible of the rules: Small creatures have 75% carrying capacity, but their equipment weighs 50% as much. So small creatures actually have more leeway with their weapons and armor weight than medium creatures.

[Fizban]

That's actually true to real life: the square/cube law refers to how the strength of bone (and possibly pulling strength of muscle?) is based on the area (a squared figure), while weight is based on volume (a cubed figure), so the bigger things get the less they can carry relative to their size. Insects can carry many times their own weight, while whales suffocate under their own weight without seawater to hold them evenly afloat.

So indeed, with lighter blades and less surface area to cover in armor backed by basically the same force, Small creatures in dnd have the advantage. Add in the fact that goblins and kobolds literally breed and reach mental maturity faster, and the Medium races are only in power by fiat of having organized and climbed the tech tree first.

[Vaern]

Funny foible of the rules: Small creatures have 75% carrying capacity, but their equipment weighs 50% as much. So small creatures actually have more leeway with their weapons and armor weight than medium creatures.

More leeway in the way of weapons and armor, yes, but a good amount of miscellaneous adventuring gear like rope and torches will weigh the same regardless of your character's size. The same applies to miscellaneous magical items. For example, I actually bought a bag of holding so that my party no longer needs to worry about the weight of the loot we collect, but the weight of the bag itself is ironically too much for me to comfortable carry.

[Knaight]

There's two major effects here.

One is that you're basically going to have to rewrite the MM, which gets really fun once size differences get pulled into this. The other is that strength is much easier to boost than constitution, which is going to inflate HP dramatically.

Splitting attack and damage between Dex and Str also causes major problems through the MM, starting with how basically every big monster can't hit anything anymore. It also causes size scaling problems throughout.

Your party being low optimization minimizes these issues a bit, as does the core only limitation - mostly because there's just less content that you'll need to rework. Still, it's a level of work close to making a whole new system.

[zergling.exe]

There's two major effects here.

One is that you're basically going to have to rewrite the MM, which gets really fun once size differences get pulled into this. The other is that strength is much easier to boost than constitution, which is going to inflate HP dramatically.

Splitting attack and damage between Dex and Str also causes major problems through the MM, starting with how basically every big monster can't hit anything anymore. It also causes size scaling problems throughout.

Your party being low optimization minimizes these issues a bit, as does the core only limitation - mostly because there's just less content that you'll need to rework. Still, it's a level of work close to making a whole new system.

I was planning on leaving the base MM enemies alone, and only applying the changes to custom made monsters. Big monsters might need some Dex adjustment or perhaps a Weapon Finesse equivalent that makes attacks go off Str rather than Dex.

[ben-zayb]

What I can see happening:
1. DEX-based characters will be less MAD by having STR as the usual secondary stat. However, most races that have +DEX also have -STR, so they pretty much get Elf stats with this.

2. Offense-oriented STR-based characters gets shafted due to lower attack bonus. I can see chargers being DEX-based instead, relying more on PA for damage.

3. Defense-oriented characters, such as Knight and Crusader, would also be less MAD by not having to juggle STR, DEX and CON. Having DEX as a default secondary score makes getting Combat Reflexes easy, and the to-hit makes you no longer feel guilty boosting it so much just to get more AoO.

4. The added utility of having STR as a secondary stat would definitely help in the early levels of casters for encumbrance. Those relying more on attacks (gish, touch attackers, ranged touchers) still need to juggle between STR and DEX. That said, at the end of the day, the casters will still, for the most part, just care about one or two scores.

Splitting attack and damage between Dex and Str also causes major problems through the MM, starting with how basically every big monster can't hit anything anymore. It also causes size scaling problems throughout.

That hyperbole doesn't really work because BAB is still a thing.

[Knaight]

That hyperbole doesn't really work because BAB is still a thing.

It works just fine. They're calibrated to hit things at their given CRs assuming current bonuses. Those bonuses routinely shrink by 15 or more.

[TotallyNotEvil]

Honestly? Seems like a whole lot of work for very little gain.

Not all stats need be useful for all characters. If you want pure caster types to care about Strenght, start carefully tracking their gear's weight.

Realistically, what do you expect to achieve with this change?

You are sort of modifying the very foundations of the system here.

[zergling.exe]

It works just fine. They're calibrated to hit things at their given CRs assuming current bonuses. Those bonuses routinely shrink by 15 or more.

A decrease of 15 would require a difference of 30 points between Str and Dex. Dragons are about the only creatures with that kind of discrepancy, and even most of them don't quite reach that. Most seem to vary between 10-16 points, so a loss of 5-8 is the norm. The biggest loss is on the colossal dragons, which go from their 47 Str to 10 Dex.

Honestly? Seems like a whole lot of work for very little gain.

Not all stats need be useful for all characters. If you want pure caster types to care about Strenght, start carefully tracking their gear's weight.

Realistically, what do you expect to achieve with this change?

You are sort of modifying the very foundations of the system here.

Create more well rounded characters.

[MichielHagen]

Honestly? Seems like a whole lot of work for very little gain.
Not all stats need be useful for all characters. If you want pure caster types to care about Strenght, start carefully tracking their gear's weight.
Realistically, what do you expect to achieve with this change?
You are sort of modifying the very foundations of the system here.

Mostly this.
But if i wanted to make a similar change, i would take the average of certain stats to determine certain aspects.

For example:
Bonus HP is determined by the average of CON and STR (round up if CON is higher than STR)
Will Save is determined by the average of WIS and CHA (round up if WIS is higher than CHA)
Amount of Skills is determined by the average of INT and CHA (round up if INT is higher than CHA)

But, as said above, it seems like you are trying to fix a problem, that is one of the smallest problems this game has, if it can even be considered a problem at all.
With the first example, you will mostly help STR-based melee characters (only slightly, if at all) and penalize casters, which might be what you are looking for.