5e Houserule: Body Type

Following up last week's heavy article on homebrew design philosophy, let's play around a little! Here's an extremely simple house rule I made for 5th edition. All it does is allow people to very slightly tweak their base ability scores during chargen, but it does so in a deliberate and meaningful way that adds depth and detail to who your character is and what they look like.

Body Type

In reality, different people will be better or worse at certain types of physical activities due to subtle variation in their physical proportions, fat distribution, and muscularity. Heavy people have more weight to throw around in labour and combat; tall people can see over obstacles others cannot, large people can handle more harmful chemicals before feeling side effects, etc.

This rule aims to apply these subtle effects of shape to the game by slightly tweaking your ability scores during character creation. The terminology used by this rule is taken from the Somatotype theories by William Sheldon, but honestly has nothing to do with those theories beyond cannibalization of his terminology. Somatotypes are used here simply as broad categorizations of human form for the sake of simplifying an honestly extremely complex subject. They also have the advantage of being extremely subjective, something RPGs thrive on, as opposed to clinical and objective like genuine scientific theories.

This is all based on human anatomy, so there is no justification to apply it to any other race. On the other hand, there's also really no reason not to! I've always wondered why there's no fat elves or tall dwarves.

Choosing Your Build

Your character's build is decided after you assign your abilities and have chosen your race/class/background templates. Your build is designed somewhat like your character alignment, but actually represents physical appearance. It has two parts, your primary body type and your secondary body type.

Your primary body type gives a +2 ability score adjustment to one of your three physical abilities. Your secondary body type gives a -1 ability score adjustment to two of your ability scores. There are only three body types, but you can have the same body type in both categories if you wish.

The combined body types are called your "build". Each of the body types are given some flavour text to give explanation of what they represent, but do not take these as being valid medical representations of how the human body actually works- I am quite literally pulling it out of thin air.

Endomorph

• Primary: +2 Constitution
• Secondary: -1 Strength and Dexterity

Endomorphs are characterized by a slow metabolism, with a body chemistry which emphasizes storage of unused energy as fat and a particular avoidance of using stored energy. This gives endomorphic bodies many fundamental advantages in nature.

1. It allows them to survive through periods of drought and famine, as their bodies have extra energy to feed off of when food is scarce.
2. It adds physical bulk, allowing them to handle higher quantities of poisons, such as alcohol, before feeling side-effects.
3. Fat is lighter than water, helping them swim or stay afloat for longer if they are trapped on the water.
4. Fat is an external layer, and is effectively a sacrificial layer of armor; an animal or weapon tearing into a fat layer is less likely to strike an important blood vessel, muscle, or tendon- a fact used by gladiators to survive armed combat without armor.
5. Fat is still heavy, and gives you more weight to throw around when you are working and fighting, reducing the demand on your muscles in certain types of work.

Because of the many advantages of being endomorphic, the vast majority of humans are at least partially of this body type; they're simply the most likely to survive.

Unlike the other two body types, which have very low tolerance of fat, endomorphic body types are built to sustain a baseline fat layer. If they use up this fat layer, the side effects are nearly identical to those of being overweight; increased blood pressure and risk of heart disease being the most prominent effects.

Endomorphs are not necessarily round or pudgy; most of them have a naturally box-like shape, bulky, but not round. An endomorph who is partly ectomorphic will likely be of the "big and tall" shape, like an upright standing cigar, while endomorphs who are partly mesomorphic are likely to be described as being "built like a brick".

Ectomorph

• Primary: +2 Dexterity
• Secondary: -1 Strength and Constitution

Think skin and bones. The ectomorphic body type is characterized by a hyperactive metabolism which tries to use every bit of energy it gets as soon as it gets any. This body type is designed to make use of any energy it can find, rather than store it, on the off-chance that stored energy may be wasted later, as it is harder to extract once stored. Because of their body's desire to make productive use of every scrap of energy and material, most ectomorphs grow rapidly during adolescence, and most of the taller folk in a population will likely be partially ectomorphic. The advantages of being ectomorphic are,

1. The added height and limb length allows them to use leverage within heir own skeletal frame to do work other body types cannot.
2. Longer legs allow a more efficient gait, and the absence of any bulk to burden or restrain movement makes running easier.
3. Most animals gauge their opposition by size alone, and they gauge that mainly by height; being a bigger person makes you less likely to be the initial target of a predator.
4. They get the greatest use out of adrenalin, allowing ectomorphs to pull feats of strength which would shock pure mesomorphs who focus on building physical strength.

Because being ectomorphic has almost as many advantages as being endomorphic, it is the second most common body type among humans, and most people are a mix of the two.

Ectomorphs need to be careful about their diet. Because their body uses everything it's given, the signs of malnourishment can be more subtle, making it hard to realize when ones diet is making one more susceptible to disease or fatigue. Ectomorphs also have little tolerance for body bulk, with their natural fat layers being extremely limited. It is important for ectomorphs to remain active, as it is very easy for them to become overweight.

Ectomorphs who are partly endomorphic are pretty much the most common human form, often called the "pear" shape, it is characterized by an otherwise ideal human form with a round tummy. Ectomorphs who are partially mesomorphic are often considered to be almost as physically ideal as pure mesomorphs, being tall, slender, and with defined muscles.

Mesomorph

• Primary: +2 Strength
• Secondary: -1 Constitution and Dexterity

Mesomorphs are characterized by a somewhat inefficient metabolism. This body type doesn't emphasize the usage or storage of energy in any particular way. Rather, a mesomorphic body type focuses on building muscle mass as quickly and efficiently as possible for as little provocation as possible. This has some obvious advantages, but they are comparatively limited, and most of the advantages are double-edged swords. This makes mesomorphs the least common body type among humans. Their traits are,

1. Increased muscle mass means you are simply stronger. Better grip and lifting are clear examples of how this would benefit a person, as opposed to the mere pushing and momentum force used by endomorphs.
2. Muscle is heavier than fat so, though it won't hold you up in water, you don't need as much bulk to get the same amount of weight to throw.
3. Muscle mass is added bulk, so it also increases resistance to poisons somewhat, but will not reduce impact, so much as delay it.
4. Your body can consume muscle for energy like fat, but this is extremely hard on your body, and ultimately counter-productive and unsustainable.

The main reason the mesomorphic body type remains, is that it allows some individuals to survive taking a "fight" reaction, where others would flee. Aside from the law of the jungle, mesomorphs can get a lot of physical work done compared to individuals of other builds, making them particularly useful to premodern society.

Mesomorphic bodies have a high tolerance for body bulk, but very low tolerance for fat, which it uses as quickly as it can. Because they have an inefficient metabolism, day-to-day variation in diet and activity can have considerable impact on body weight, shape, and health. This means mesomorphs need to be the most cautious about their diet and maintain a fair degree of day-to-day activity in order to maintain a healthy weight.

Mesomorphs who are slightly ectomorphic are the classic Roman ideal; tall and muscular, like a greek god. Mesomorphs who are somewhat endomorphic are built like classical gladiators, muscular and bulky, like a bull in human form.

Handling Build

After choosing your build, it is displayed as the two prefixes separated by a slash, in order of primary/secondary. So for instance, if a character is primarily endomorphic and secondarily ectomorphic, their build would be Endo/Ecto.

Once every game year, a PC may change their secondary body type. They may change their primary body type once every ten years. This is intended to represent natural changes in how the body works as one ages. For example, a person may be Ecto/Ecto as a child, Ecto/Meso as an adolescent, Meso/Meso as an adult, Meso/Endo in maturity, and Ecto/Endo in old age.

This does not represent the effects of ones diet on body shape, only the body shape their body wants to be. Nothing will stop you from being morbidly obese if you eat seven meals a day and never leave your bed, or frighteningly gaunt if you don't eat for two weeks.