Unusual Characters; balancing on four legs – or no legs
Before I get into this, I’d like to remind everybody that we have scheduled downtime on the 10th; the Portal and the Oracle will be down for maintenance.
If you’ve been GMing for very long, you’ve probably had someone come to you with a character, or a template that they really, really wanted to play with, usually involving an exotic race that may or may not even exist in the setting you’re using. Naga, lamia (feline or serpentine), or driders .. centaurs can include merfolk, harpies, girtablilu, cecalia and bariaur. Some might even count satyr and fauns, and they’ve all got their own unique challenges in play.

How you handle that really depends on your group and your setting (Pathfinder allows for almost all of the above, and adds some new ones for spice, Krynn has the centaurs and some other options not named. Faerun of course, has most of them…), but in the end, the choice is going to be yours. Many of these races are more powerful than standard PCs – the lamia and driders particularly – and you have to balance that with a probably-human-centric group. This is likely to result in a high-level campaign, unless you split racial powers into levels – 3.5e has rules for that – and even then, you will have to think long and hard about what it means to a character to not have class levels in those first few levels unless you are using gestalt rules.
Now, I have played a character that ended up being one of those exotic races (a dragon. We played a round of Resurrection Roulette and I rolled box cars), and let me tell you, that was a balancing nightmare. We learned all sorts of new things about how to make a character like that work in a group, and we eventually ended up using gestalt rules just to bring the character down to a usable power-level, if we hadn’t, I would have had access to ninth-level spells.
That was a mess; we use Hero Labs, and it really doesn’t do racial levels in a way that makes them work with gestalt rules. Now, that was a dragon; dragons are higher-powered again than anything I listed above, but the example of balancing and special requirements stands.
Using Pathfinder’s Lamia – just the standard lamia, not the Matriarch or Harridan – you are looking at a character that is going to start at level nine, just from racial levels. She comes with magic – fairly powerful magic, including shapeshifting – and a not insignificant toughness of her own, just being what she is. That’s before you start adding on class levels. So, you have a Large creature who’s base speed is 60′, who comes with a powerful stat-spread – she could be almost anything, but is particularly well set up for martial classes, or wisdom-based spell-casting – and a spread of spells best used to distract or disable opponents. Add class levels to that; let’s say for gits and shiggles, you make her a paladin.
Spellcasting. Martial prowess. Armor, and mobility, on top of her natural agility. That’s one holy warrior I would not want to be on the wrong side of.
That having been said, there are other things you need to consider. That lamia, even built as a paladin of Shelyn, is going to have trouble in most cities thanks to their well-earned reputation for being evil, after all. Now, lamia can shapeshift and avoid many of the social issues, but if your player wants to run something else that does not possess that ability natively you will have to give a few things some very careful thought; where is the campaign going? Can a large creature even fit in most of those spaces? Is that character going to have trouble in social encounters? Even if you aren’t playing in Golarion, a Faerunian drider is going to have a hell of a time on the surface, and that’s even with that sappy ranger flitting about. The rest of the group should probably not be surprised – out of character, anyway – they should be allowed to discuss it and decide what, if any, background hooks exist that will make it easier to integrate the exotic character.
Then you have to remember that most centaurs, lamia, driders .. whatever, most of them are Large creatures by default (as the GM, you can modify this, if you wish). Even if you do not, however, they will still need special gear; armored barding for their lower halves, special boots or shoes for feline lamia or centaurs. Equine or cervine centaurs have other special needs; hooves require special maintenance, and usually a second pair of hands. Getting a centaur of any type into and out of armor is almost always going to take help; most of them won’t easily be able to reach their own back ends.  Almost always, one of these characters will weigh significantly more than their two-legged compatriots, and may have trouble doing things that smaller, lighter two-leggers don’t think about. Ladders come to mind. Climbing ropes also comes to mind.
Gear for quadrupeds isn’t something most systems cover very well. There is a supplement for Pathfinder and – I think – for 4e, and possibly 5e, designed specifically for playing quadrupeds. It covers assorted kinds of ponies and griffons and touches briefly on dragons, and may be of assistance for gear, equipment slots and other tricky quadruped-only issues and I cannot recommend enough picking up the resources you need to make the thing work.
I would be surprised if there weren’t others, and I invite you all to tell us what you use, what you’ve seen and any stories you have about that one time in the dungeons.
(We do not get money from Lone Wolf Development, we just really like their toys. Nobody is paying us to mention them, much less to link to them.)