Wheeled Warfare

[Polycarp]

Wheeled Warfare
A Cooperative Charioteering Mega-Thread
Or, "Ghost Riding the Chariot"

Chariots were of incomparable military, political, cultural, and symbolic importance to many early human cultures.  Chariots, however, are rarely mentioned in mainstream d20 (Iâ,¬,,¢ve heard that Sword and Fist devotes what amounts to a few paragraphs to them).  I know I could go buy Sword and Fist for their snippets of info, but Iâ,¬,,¢m cheap, and Iâ,¬,,¢m ok with â,¬Å"re-inventing the wheelâ,¬Â (that was a chariot pun, and probably not the last one).  I would rather create a system that makes sense to me from the ground up, and embellish that system with the items, spells, prestige classes, and other bonuses that it needs.  I am of the opinion that mounted combat generally is given the short shrift by WotC, not to mention chariot combat.  This post â,¬' and hopefully, my posts that will follow â,¬' will explore d20 chariots in detail, approaching them from a largely â,¬Å"crunchâ,¬Â perspective.  I donâ,¬,,¢t often foray into the world of crunch, so this will be something very new for me â,¬' and, if you havenâ,¬,,¢t played games with chariots, it will hopefully be something new for you too!

Though crunch is the focus here, sometimes a little fluff is called for.  When I get to chariot-related magical items for instance, Iâ,¬,,¢ll probably include a â,¬Å"fluff blurbâ,¬Â on the item like most splatbooks would.  When I do this, Iâ,¬,,¢ll be referencing my own campaign world, but except for such fairly minor fluff references I intend to design everything here for general use in any d20 campaign.

I must emphasize the cooperative nature of this effort.  I invite critique, additions, changes, and so on - I'm thinking through this as I write it, not just posting what I've already decided on.  Your comments on mechanics, your ideas for items/classes/spells, and so on are all welcome and encouraged.

Part 1: Chariot Mechanics

No, not guys who fix chariots â,¬' the rules of how chariots function in game terms.  Iâ,¬,,¢m building this system from the ground up, based on SRD rules for mounted combat.  Without further adoâ,¬Â¦

First, the basics.  For our present purposes, a chariot is a one-axle, two-wheeled rolling platform carried by two horses that can be used for racing, war, or transportation.  We may touch on variants later â,¬' like a Hittite style 3-man â,¬Å"heavyâ,¬Â chariot, Sumerian 4-wheelers pulled by asses (which should really be called carts, not chariots), and Roman quadrigas with 4 horses â,¬' but for now weâ,¬,,¢re keeping it simple.

Because carts and wagons are covered under the Handle Animal skill, chariots will be too.  Weâ,¬,,¢ll be using Handle Animal as a kind of Ride skill, however, which necessitates making some changes to Handle Animal.  The first is that Handle Animal is a Charisma-based skill; while that makes perfect sense for the usual use of the skill (training an animal), it is a less than optimal choice for charioteers.  Dexterity would probably be a better alternative, so Iâ,¬,,¢ll use the variant rule that, when the Handle Animal skill is used for charioteering, a character uses their Dexterity modifier instead of their Charisma modifier.

Next, we need to look at the mechanics of the Ride skill itself and translate them into Chariot-ese.  These are the standard uses of Ride (along with their DCs) as per the SRD:

Guide with knees 5
Stay in saddle 5
Fight with warhorse 10
Cover 15
Soft fall 15
Leap 15
Spur mount 15
Control mount in battle 20
Fast mount or dismount 20

Some of these are not workable.  You canâ,¬,,¢t guide a chariot with your knees.  Ordinarily, the driver has both their hands on the reins, but perhaps this function could be changed to â,¬Å"Drive with one hand,â,¬Â allowing you to operate the chariot with one hand while leaving the other free to fight (or whatever hands do).

â,¬Å"Stay in saddleâ,¬Â is a check to avoid falling out if your horse bolts, or whenever you take damage.  It can be easily translated into â,¬Å"Stay in chariotâ,¬Â with the same DC.

â,¬Å"Fight with warhorseâ,¬Â normally allows you to attack on the same round that your mount attacks.  This can stay in as is.

â,¬Å"Coverâ,¬Â has to go, because you canâ,¬,,¢t drop down by the side of your horse if youâ,¬,,¢re riding in a chariot.  The use of the skill is also redundant; war chariots have â,¬Å"wallsâ,¬Â that should protect enough to afford the passengers cover.  This use of the skill will be removed.

â,¬Å"Soft fallâ,¬Â is useable because you can just as easily fall from a chariot as you can from a horse.  It can stay in as is.

I donâ,¬,,¢t really think a chariot can leap; it seems a bit unwieldy.  Maybe somebody with more experience in chariot physics will prove me wrong, but for now Iâ,¬,,¢ll get rid of this use of the skill.

â,¬Å"Spur mountâ,¬Â is a great use of the skill, especially for chariot racing, and can be left in as is.

â,¬Å"Control mount in battleâ,¬Â is used to control normally untrained steeds.  Because itâ,¬,,¢s certainly possible to have a riding chariot with steeds unused to war, this can stay in.

â,¬Å"Fast mount or dismountâ,¬Â can also be included as is.

Some of these usages will have to be pluralized, which requires another tweak of the rules.  If the rider decides to â,¬Å"controlâ,¬Â his untrained horses while in combat, does he have to make checks for both his steeds?  In the interest of simplicity, letâ,¬,,¢s rule that both steeds function as one for purposes of the skill.  Only one check is necessary to spur or control the mounts, and the skill usage affects them the same way; when spurred, for example, both mounts take damage equally.

Here is our completed Handle Animal skill use chart:

Drive with one hand 5
Stay in chariot 5
Fight with warhorses 10
Soft fall 15
Spur mounts 15
Control mounts in battle 20
Fast mount or dismount 20

Of course, we might want charioteers to have their own cool tricks like â,¬Å"coverâ,¬Â and â,¬Å"leap.â,¬Â  If anybodyâ,¬,,¢s watched Ben Hur or another movies with chariots (I havenâ,¬,,¢t), feel free to propose any special moves you think a charioteer could execute.

Now for our basic feat tree, which is basically the same as the Mounted Combat feat tree:

Chariot Combat (req. HA 1 rank)
Chariot Archery (req. HA 1 rank, Chariot Combat)
Trample (req. HA 1 rank, Chariot Combat)
Drive-by Attack (req. HA 1 rank, Chariot Combat)
Chariot Charge (req. HA 1 rank, Chariot Combat, Drive-by Attack)

Despite the fact that â,¬Å"Drive-by Attackâ,¬Â sounds like something out of Grand Theft Auto, we have ourselves a good starting feat tree.  Again, this may be added on to later.  One of these feats, however, requires closer attention: Trample.  When you get trampled by a chariot, itâ,¬,,¢s not just one horse, but two horses, and a pair of wheels.  The SRD states for Trample:

When you attempt to overrun an opponent while mounted, your target may not choose to avoid you. Your mount may make one hoof attack against any target you knock down, gaining the standard +4 bonus on attack rolls against prone targets.

A breakdown of this partâ,¬,,¢s questions:[/b]
How should wheel trample damage work? Automatic hit, or an attack roll?  How much damage?
What are some other uses for the Handle Animal skill and Chariot feats?
How can we reflect that historically, chariots donâ,¬,,¢t do well on rough ground?  Maybe a check to travel over rough ground or obstacles is in order.
Can chariots jump?

[Wensleydale]

Although this looks mostly workable, I would say that surely balance should play at least some part in the chariot. Perhaps balance for Stay in Chariot, at least. Handle animal looks good for the others, although if we didn't mind multiple-skill-dependency, I would say tumble for soft fall too. ;)

[snakefing]

Hmm, my first thought is that chariot driving almost needs a separate skill. Not that Animal Handling is bad but... While I can imagine that your average person with Animal Handling skill would be good enough to drive a cart or wagon, I'm not sure I can say the same for driving a chariot pell mell across open terrain. Similarly, though there are some similarities to Ride, I'm not sure that a person with Ride skill would just be able to jump on a chariot and be a competent driver.

You could either create a new skill for it, or if not, I'd use Ride and give a person who is not used to chariots a -4 on their checks until they are trained on them.

Fluff would be good, for those of us who haven't done much reading about chariot warfare. I've got at least one culture in my world that uses war chariots and it is on my research list, so anything you (or anyone else) can throw out there is helpful.

[Polycarp]

Although this looks mostly workable, I would say that surely balance should play at least some part in the chariot. Perhaps balance for Stay in Chariot, at least. Handle animal looks good for the others, although if we didn't mind multiple-skill-dependency, I would say tumble for soft fall too. ;)

Alright, that's a possibility.  There a few things two consider here.

The first is that the Ride skill eschews this.  For an extreme example, there is an Epic level Ride usage that lets you stand on your mount while it's moving around.  Presumably, standing on a galloping horse without falling off would be linked with balance, but it is subsumed under Ride because it has to do with riding.  "Pushing" your horse could be considered a handle animal skill, and soft fall a tumble skill (as you said).  Really, the entire Ride skill could be broken into Handle Animal, Balance, and Tumble components; there isn't a single usage of Ride that couldn't be altered in that way.

The question, then, is why is Ride a separate skill.  Part of it is probably simplicity; the Paladin only has to worry about his Ride skill, not an assortment of HA, Tumble, and Balance.

The second reason is that diversifying the skills changes the dynamics of the skill dramatically with regards to class.  Who has the Ride skill as a class skill? Primarily warrior types (barbarian, ranger, paladin, fighter), plus the Druid.  In core D&D, warrior-types (and druids) will be the best riders.

Who has Handle Animal as a class skill?  Interestingly enough, the same exact classes.  The warriors plus the Druid.  That was one of the reasons I chose Handle Animal; it preserves the established role of the warrior-types (plus Druid) as the best riders.

Who has Tumble and Balance as class skills?  None of the "Ride emphasis" classes.  These skills are both given as class skills only to rogues, monks, and bards, classes that are not established riders, and classes that probably have the least to gain from being on a speeding chariot.  It makes intuitive sense to have Balance let you stay in the chariot, and have Soft Fall linked to Tumble, but as you can see it also changes the dynamics significantly - it makes the traditional riding classes mediocre charioteers at best, and makes classes that are traditionally bad riders pretty good at it.  In fact, no single classed character could master all the neccessary skills, because as far as I can tell, no core class has both Handle Animal and Tumble/Balance as class skills.  I am hesitant to apply Tumble and Balance for these reasons.

Hmm, my first thought is that chariot driving almost needs a separate skill. Not that Animal Handling is bad but... While I can imagine that your average person with Animal Handling skill would be good enough to drive a cart or wagon, I'm not sure I can say the same for driving a chariot pell mell across open terrain. Similarly, though there are some similarities to Ride, I'm not sure that a person with Ride skill would just be able to jump on a chariot and be a competent driver.

It's a good point, and a case can certainly be made for a "Charioteering" skill.  Charioteering, however, would be a very esoteric skill.  In the World of Ralum (my campaign world), there is almost no horseback riding and a whole lot of charioteering, so it could make sense.  In most other standard campaign worlds, however, chariots would probably be fairly rare compared to horses; as you commented, you have "at least one" culture that uses war chariots.  My guess would be that most campaign worlds using this material would be similar - chariots would be present in one or two cultures, or encountered from time to time, but not really the focus of the action as in Ralum.  As I intend this as a viable system for every campaign, even those who just want a little splash of chariot, I'm not sure making Charioteering its own class would encourage people to take it.  At least Handle Animal has enough other uses that characters would not worry about "wasting" ranks in a skill that might not come into play very often.  Handle Animal is also a seldom-used skill itself (in my experience), making the addition of charioteering to it an added bonus for those that ordinarily might go for another, more generally useful skill.

I like the idea of people with the Ride skill using chariots at a penalty (and vice versa, maybe), but -4 isn't enough.  The SRD states that you take a -5 penalty to Ride when riding bareback, and I would assume that a skilled rider would be more comfortable riding bareback than riding on a chariot, something he may not have even done before.  I think the penalty must logically be at least -5.

[quote1170270643]Fluff would be good, for those of us who haven't done much reading about chariot warfare. I've got at least one culture in my world that uses war chariots and it is on my research list, so anything you (or anyone else) can throw out there is helpful.
[/quote]

Ok, I will include more in future iterations.  I'm going to use some fluff examples once the combat system is more complete, to illustrate the maneuvers and actions we're working on.  What kinds of fluff are you interested in?

[Epic Meepo]

Why not just treat the entire chariot-and-horses team as a single creature and use the Ride skill more-or-less normally? Perhaps "chariot team" could be a template applied to two horses and a chariot, giving them a bigger space, more trample damage, and a slower speed (due to encumbrance).

[snakefing]

I think you might also need to consider the lower maneuverability of a chariot, although that might be unnecessary complication. Overall, you could probably treat driving a chariot a lot like using Ride skill for unusual mounts.

I'd be interested in all kinds of historical and military perspective on chariots.

Construction: What variations are there? What kinds of raw materials? Were chariots ever actually built with blades on the wheels, or is this a Hollywood invention? Inquiring minds want to know.

Military: The role of chariots would be somewhat analogous to mounted cavalry, I'd think. That is, largely heavy shock troops to break up enemy formations, or perhaps some lighter chariots that can attempt to outflank opponents. What are the relative advantages and disadvantages of chariots vs. cavalry? What kinds of weapons are typically used by the charioteer? What kinds of tactics can you use to oppose chariots?

Racing chariots: Gee, I don't even really know what to ask about here. For racing I think of Roman stadium stuff, like Ben Hur, but when I think of war chariots I tend to think of Egyptians, Hittites, and Assyrians. Did they have chariot races? Do we even know?

Were chariots often (or ever) used as transportation? I could imagine a highly elaborate chariot as an ostentatious showoff piece, but it seems uncomfortable and unwieldy as a means of getting around. Even if someone else is driving, I'd think it would be a little hot and dusty.

Anyway, there are some questions.

[Polycarp]

Wow, I'm really impressed at all the feedback this soon!  I'm going to address snakefing's fluff questions first.  I need to note first of all that I am not an expert, and that I am digging up stuff from my memory here, not from a textbook at my side, so my answers may not be 100% correct.

Chariots were used as a weapon of war and as a means of transportation for millenia.  They begin appearing in history in the 2nd millenium BC; their heydey was at the Battle of Kadesh (around 1300 BC), between the Egyptians and the Hittites, in which thousands of chariots were utilized by each side.  This was in an age before cavalry; horses of the time were too small and weak to carry an armed (let alone armored) rider.  As horse breeding yielded more and more capable warhorses, however, horseback cavalry began to replace the chariot.  The "last gasp" of chariot warfare was at the Battle of Gaugamela in 331 BC, when Alexander the Great's well-trained troops humiliated the Persian chariot corps, which failed utterly to inflict any real damage on the Macedonians.  They continued to be used afterwards by the Celts in Europe, though usually to little effect against the Roman legions.  They enjoyed a much longer lifespan as a ceremonial vehicle (the Romans used them in parades) and as a racing machine; chariot racing was common in the Roman and later Byzantine Empire for centuries after they became obsolete for warfare.

Construction: What variations are there? What kinds of raw materials? Were chariots ever actually built with blades on the wheels, or is this a Hollywood invention? Inquiring minds want to know.

Military: The role of chariots would be somewhat analogous to mounted cavalry, I'd think. That is, largely heavy shock troops to break up enemy formations, or perhaps some lighter chariots that can attempt to outflank opponents. What are the relative advantages and disadvantages of chariots vs. cavalry? What kinds of weapons are typically used by the charioteer? What kinds of tactics can you use to oppose chariots?[/quote]Racing chariots: Gee, I don't even really know what to ask about here. For racing I think of Roman stadium stuff, like Ben Hur, but when I think of war chariots I tend to think of Egyptians, Hittites, and Assyrians. Did they have chariot races? Do we even know?[/quote]Were chariots often (or ever) used as transportation? I could imagine a highly elaborate chariot as an ostentatious showoff piece, but it seems uncomfortable and unwieldy as a means of getting around. Even if someone else is driving, I'd think it would be a little hot and dusty.[/quote]

Chariots were used for transportation in, to, and from battle; noblemen probably could have used them for regular transport, depending on how fast they needed to go.  I don't really know to what extent they were used to just "get around," I would assume most noblemen just had their servants carry them around in a sedan chair or something.  Later chariots used rope or leather straps to form the first example of what we would call a "suspension," making them far easier to drive, safer to ride in, and more comfortable for all involved, but chariots without such suspensions were probably pretty jarring to ride around in a lot.

Sumerian art depicts early "chariots" (actually carts, since they had four wheels) drawn by onagers.  It is unclear whether they used these as heavy chariots in battle, or whether they were strictly for transportation and supply duty.

[Stargate525]

I'm quite surprised no one has thought of the idea I have as far as skill checks are concerned. I would suggest pulling the drive skill out of d20 modern, and making that cover all moving vehicles, moving cart driving out of handle animal. This would let you customize the whole shebang, and allow a skill roll to be applicable for a full range of similar devices, as is the ride skill.

I agree that the two(or four, or however many) horses should be treated with one check. if I recall correctly, horses were trained in teams specifically for the purpose of pulling side by side. I'd impose a penalty if the horses were not trained in this way.

Were chariots ever actually built with blades on the wheels, or is this a Hollywood invention? Inquiring minds want to know.

They were, actually. They would attack long scythe-like blades sticking out of the wheels, which would spin and mow down enemy infantry much like a modern reaper would a field of corn. These came about very near the end of the life of the chariot, so were not seen in battle that often, but I imagine they would be absolutely astounding death machines.

What are the relative advantages and disadvantages of chariots vs. cavalry?

Well, you can't kill a chariot. By that I mean that even if the chariot is rendered inoperable during the battle, you can still repair it and have it in service by the next battle. You can't do that with horses. Also, with larger chariots you could fit two or three people on it, only one of which has to pay attention to driving. This frees up the others for concentrating on attacks.

What kinds of tactics can you use to oppose chariots?

The wheels were by far the weakest point. Being very narrow for the weight of the chariot, they were prone to getting stuck in soft earth and mud. Getting moist soil with magic would probably not be difficult. The second weakness was the horses. Killing one eans you at least temporarily disable the chariot, as they now have a corpse dragging along the ground.

Were chariots often (or ever) used as transportation? I could imagine a highly elaborate chariot as an ostentatious showoff piece, but it seems uncomfortable and unwieldy as a means of getting around. Even if someone else is driving, I'd think it would be a little hot and dusty.

For that you need to more closely define what you mean by chariot. There were four-wheeled   pleasure carriages known as chariots as well.

[Polycarp]

Why not just treat the entire chariot-and-horses team as a single creature and use the Ride skill more-or-less normally? Perhaps "chariot team" could be a template applied to two horses and a chariot, giving them a bigger space, more trample damage, and a slower speed (due to encumbrance).

Hm, that could work.  It might be harder to use localized effects on this one (that is, damaging the chariot or wheel, or attacking a horse, or trying to continue driving with one horse).  I'm not very familiar with using templates for multiple creatures but it seems plausible.

I think you might also need to consider the lower maneuverability of a chariot, although that might be unnecessary complication. Overall, you could probably treat driving a chariot a lot like using Ride skill for unusual mounts.

I intend on addressing maneuverability in the next section; I just wanted to get basic skills and feats out of the way first.

Ride (chariot) would work, I'm just concerned that having such a limited class would make people unlikely to take it.

Actually, having different ride skills for different mounts is a 3.0 rule, I think.  THe 3.5 SRD (I'm just noticing this now) says:

If you attempt to ride a creature that is ill suited as a mount, you take a -5 penalty on your Ride checks.

What if the "Chariot Combat" feat was made so, in addition to the normal rules for Chariot Combat, it also eliminated the -5 penalty normally taken for riding something a chariot, normally considered "ill suited as a mount?"  That way, you could use the same Ride skill, and an experienced rider could still use a chariot at -5 (enough to do basic things), without requiring a whole new skill for charioteering.

I'm starting to lean towards changing the skill from HA to ride.  Any other opinions on the issue?

Also, should charioteering have a separate feat tree?  Maybe the Mounted Combat feat tree should cover chariots as well, especially if they both start using the same skill.

[Polycarp]

I'm quite surprised no one has thought of the idea I have as far as skill checks are concerned. I would suggest pulling the drive skill out of d20 modern, and making that cover all moving vehicles, moving cart driving out of handle animal. This would let you customize the whole shebang, and allow a skill roll to be applicable for a full range of similar devices, as is the ride skill.

Again, my reservation about doing this is that for most campaigns, this will be a very limited use skill.  From what I've seen, the typical campaign has carts and maybe some chariots now and then, assuming a few cultures still keep them around.  A DM might see this thread and think "oh, some chariot racing would be fun" or "maybe I could get the PCs to visit this ancient land and fight with chariots in this adventure," but this is unlikely to be a centerpiece in most campaigns.  One of my primary goals here is to make this system universally useable even if a DM just wants to use it in a single adventure.

So here are the present options so far:

- Use Handle Animal, with Dex instead of Cha.
- Use Ride.
- Use Ride, but with the -5 penalty, and include some way (feat?) to negate that penalty.
- Add a new skill (like Drive) and subsume all animal driven land vehicles under that skill.

What to do...

[Tangential]

As a thought. You could take Drive (or whatever you want to call it) and make it like Craft and Perform. Thus you can have Drive (land vehicle), Drive (ship), Drive (living creature) [replacing Ride] Drive (flying creature) and so forth.

Then you have several options. Include a feat that allows you to treat ranks in one form of Drive as ranks in all forms. Or allow you to take a -4 (or -5) penalty to all Driving that isn't of your subset.

[Polycarp]

Alright, here's my complete take on it.  As you may have noticed by now, I'm really long winded.  Sorry.  :shy:

I don't think the purpose of this system-in-the-making is served well by having charioteering require its own skill points; it's too esoteric.

I like the idea of having a "Drive" skill to cover multiple vehicles, and if I were making a more broad reform of the skill system I would go for it.  I want this to be an addendum, however, not a rewrite of rules that aren't chariot related.  Having a Drive skill that was actually worth taking ranks in would mean dumping things like Profession (sailor or navigator), which already governs driving ships, and Handle Animal, which already handles driving carts (not to mention Ride).  I think that a good "add-on" system should keep most of its changes internal, rather than recategorizing other skills and systems external to the add-on.

If you agree with me so far - which you may or may not, but let's say you do - the choice comes down to whether charioteering should be placed within Ride or Handle Animal.  As far as crunch goes, there's not much difference.  They are both class skills to the exact same classes.  They both use the same ability score (as per the variant rule in the first post).  Neither would overpower the skill.  Either could be made into a workable system.

If you agree with me up to this point, it means that we've come to the conclusion that it's going to be difficult to decide whether to use Handle Animal or Ride based on crunch concerns.

So I say we use fluff.

Which would better equip you to use a chariot: knowledge of riding horseback (or on any animal's back), or knowledge of... well, handling animals, including carts, ox teams, and teaching the animals tricks?  Which would make a better charioteer?

That was a poor question, because any cavalryman would have to know both the mechanics of riding and how to train and handle their steed.  The rules recognize this to an extent; there is a +2 synergy bonus to Ride if you have 5 ranks of Handle Animal.  A rider, at least, should know both in order to be a good rider.

Of course, we're not talking about riders, we're talking about charioteers.  A charioteer, like a rider, would certainly need to know the Handle Animal skill in real life; his animals would need to be well trained and he would have to know how to handle them and get them to perform, just like a rider would.  But a charioteer would not need to know about the mechanics of riding horseback, because when charioteers were in their heyday, such mechanics didn't exist.  Though as snakefing said, it's hard to see a commoner with a few ranks in Handle Animal to guide his donkey and cart to market every day subsequently hopping in a chariot and going to war, I think it's equally hard to see a herdsman on his steppe mare subsequently mounting an immense charger and going full tilt into battle.  The situation seems equally silly.

Because, therefore, Handle Animal is certainly applicable and the situation of Ride is more doubtful, and because charioteering predates the very idea of riding by a substantial margin, I think the best solution is to go with my original post and use Handle Animal (Dex) for charioteering.

How does that sound? :)

[Tangential]

I am in agreement regarding the Drive skill if you are intending this (as you are) to mesh with the current rules system.

As I read further into your post I though that you were about to argue that Ride should than govern it, and began formulating the reasons why Handle Animal should instead.

In a surprise move (:p), that used perfect logic that followed my own you came to the same conclusion regarding Handle Animal.

Handle Animal (Dex) for President.

[Captain Obvious]

Why not use a new skill but give a synergy bonus for ride/handle animal ranks to allow people that don't have the skill to do it a bit. Also for the balance/tumble bit from earlier, have the chariot skill gain synergys from those two for the appropriate skills. Synergy is a beautiful thing for customising skills.

[Polycarp]

Why not use a new skill but give a synergy bonus for ride/handle animal ranks to allow people that don't have the skill to do it a bit. Also for the balance/tumble bit from earlier, have the chariot skill gain synergys from those two for the appropriate skills. Synergy is a beautiful thing for customising skills.

I thought of the fact that Handle Animal is a trained only skill while Ride is not, and I agree that people who don't have the skill should be able to try it.  I just don't think that having a new skill for it is a good idea, even with a synergy bonus, but having synergy bonuses from balance sounds good.

I think we should use Handle Animal, with the following house rules:
1) When used for charioteering, Dex is used instead of Cha.
2) Likewise, when used for charioteering, Handle Animal may be used untrained.
3) If a character has 5 or more ranks in Balance, they gain a +2 synergy bonus to Handle Animal checks concerning charioteering.

That makes it so any character can try and use a chariot, and rogues/monks/bards with Balance will actually get a small bonus to it.  That might also encourage a character who wants to be the best charioteer ever to dip into cross-class ranks for the additional bonus.