A measurement of the amount of damage a character can take based upon their mass and experience level. Sometimes abbreviated as 'hp'. Despite the details included below, for everyday common usage of hit points, the 'total number' or 'maximum number' of hit points a combatant has refers only to the number of hit points they have above zero.
All creatures greater than 5 lbs. in weight are considered to have, at minimum, 1 hit point. Some creatures that have 1 hit point may be smaller than five pounds, such as giant centipedes, rot grub, floating eyes and so on . . . but this potential for damage is due to the special characteristics of these creatures. For the most part, the 5 lb. minimum should be the guideline where creatures are concerned. Therefore, ordinary, familiar creatures such as ordinary rats, kittens, bunnies and so on are not considered to have hit points at all, even though obviously these things can be killed. As they do not represent a threat, however, killing them brings no game reward.
All creatures that possess hit points will also possess at least 1 hit die. If a creature possesses multiple hit dice, then the number of hp that a creature will have will depend upon the creature's mass multiplied by the number of hit dice that the creature possesses. See Hit Points per Die.
Hit points are increased by all intelligent creatures through the acquisition of levels through experience. As a level is gained, the combatant increases the total number of hp they have depending upon the class of expertise to which they adhere. It is important to understand, however, how hp work and precisely what is happening when hp are increased.
Hit points are not an expression of the body getting stronger or being able to take more damage. The amount of damage that can be taken does not change because the physical condition of the body does not change. Hit points are added due to changes in the combatant's perception and skill, not due to the combatant developing a greater capacity for taking damage. It can be argued, however, that the combatant is better able to ignore damage that has been done - but this, too, is a characteristic of perception, not strength.
To better understand what a hit point is, the substance of what a hit point is must be divided between those hp acquired due to mass (the physical capacity of the body to take damage) and level/experience (the mental capacity of the body to minimize damage). This is a very important point. Hit points are not in fact increased! Damage is minimized. Having more hp is simply a means of more easily accounting for the reduction of this damage.
Biological Units (BU)For any creature, hit points per die are derived from the total weight or mass of the combatant. Since an elephant is so much larger than a human, an African elephant gains more hp per die (d4+2d6 as opposed to 1d8 for an ordinary mature human male). Moreover, as the African elephant is tougher, considerably more massive and less vulnerable to weapons, the African elephant has 11 hit dice while the human has only one. This means that a ordinary elephant (which cannot achieve levels due to its low intelligence) will have many times more hp (average 105) than an ordinary, inexperienced human. These hp that derive from mass are also called biological units.
The term BU is used to describe characteristics of creature origin, growth and structure, dependent upon the physical presence of the body as it grows and matures. BU represents that part of a combatant's total hit points apart from the skill that is eventually gained through acquiring levels.
Since the number of hit points per die (BU) for an averaged size human male is 1d8, the total potential BU for a male of this mass is 8 points above zero. However, due to the rules surrounding negative hit points, death does not occur at zero. For non-experienced creatures, death occurs at -4 hp. This means that a human male with 8 BU in fact possesses 4 more BU, from a capacity to survive with between -3 and 0 hp. See the chart below expressing the spread of BU between -3 and 8:
As we move to the left end of the scale, health declines and at -4, death occurs. As we move to the right, the creature becomes more healthy. For the human male in question, 8 is the maximum number of BU - and the maximum number of hit points without training - that the male can possess. Take note, however, that a smaller human would 1d6 hp per die, or a maximum of 6+4 = 10 (always remembering to add the negative numbers) rather than 12. A creature as large as an elephant would have 176+4 = 180. This would be the healthiest possible elephant in the world.
The benefit of beginning the scale at -3 is to divide the vitality of the creature into three categories: a) illness, in which the body's is less than zero; b) vigorous, in which the body's BU is greater than zero; and c) sapped, or exhausted, in which the body's BU equals zero. 'Sapped' does not mean that the body is ailing, only that it has reached the point where the body has become strained. Further effort is possible, but it will likely result in the body becoming ill.
We can subdivide the three degrees of the body's illness:
- -1 BU = subdued, where the individual will probably be fine if they receive bed rest. This isn't enough damage to cause to knock the combatant unconscious, but death is obviously quite close.
- -2 BU = serious, where the body has become moderately weak, with some mobility but requiring assistance. Periods of lucidity would be broken up by long periods of sleep and rest.
- -3 BU = critical, where 1 BU separates the body from death. This could be described as intense weakness, an inability to rise or tend to one's own needs, drifting in and out of consciousness (more out than in) and probably not being fully aware when awake.
Composition of BUOn the scale towards vitality, it is established that any person who is not chronically ill will have a positive number of BUs. This does not mean that everybody would be vigorous enough to possess 8 BUs. The actual number of BUs possessed depends upon the condition in which the body is kept, complimented by the condition the body possesses at birth. We can extrapolate BU as a composite of different elements that combine to form vitality - for any creature, regardless of intelligence:
- Activity: alternately metabolism, the body's capacity to transform food to energy, to enable action and the pursuit of survival.
- Depreciation: degradation of the body's health due to disease, injury and failure to successfully endure and heal from damage.
- Happiness: the state of the body and mind's freedom from distress or discontent.
- Health: the soundness of the body, freedom from chronic disease or ailment.
- Heredity: the transmission of strong genetic characteristics from parent to offspring.
- Initiative: the reaction time of the body's systems.
- Maturity: the development to peak physical development with experience and survival.
- Nourishment: the nutritional balance that has sustained the body.
There may be other possibilities, but on the whole these cover the principle aspects of life. The important thing to understand is that BUs do not derive from training or skill. The elements above do not derive from training. Training can enhance all of the above, but these things provide a measurable contribution to hit points before training can occur.
This is key. There must be some measure of each, that in turn combine to produce the number of BU that the creature possesses above zero. The combination would not be the same from individual to individual. Many creatures would have a composition that was very poor, providing them with few hit points; other creatures would have a rich composition, providing them with many hp. This is what the die determines when it is rolled randomly against the creature's total mass and hit dice.
Given this system of BUs, it is safe to argue that individual combatants would know how strong they were - and that among intelligent creatures it would be easy to identify which of their number ought to be standing guard and which would deserve to work as lackeys. Thus, when encountering large numbers in their lair, the combat trained soldiers on the front line would have hp in the upper range of the random number of hp generated; and virtually every support person (beyond personal body guards) would have less. This does not mean that the numbers were not randomly generated for everyone in the lair - only that, once each person randomly demonstrated their strengths, the lair naturally ordered itself according to each individual's strengths.
Hit Points from LevelsFor player characters, the number of BU they possess is also random, rolled for their mass. A halfling will probably have a d4 rolled while a human may have a d6 or a d8, potentially 2d4 if they are very large. Then, because they have a level, the character receives more hit points deriving from that level: d4 for mages and illusionist, d6 for thieves and assassins, a d8 for clerics and so on. Details for that can be found under Player Characters. For non-player characters these are rolled randomly. Player characters benefit from getting their maximum hp for their level upon character generation.
For example, a non-player 1st level fighter, weighing 182 lbs., would roll a d8 for their hit points derived from mass (BU) plus a d10 for their hp derived from class. The average of these rolls is 10. A player running a fighter with the same weight would still receive a d8 for their mass hp but would automatically receive 10 hp (the maximum), to ensure the player's fighter begins with above average hp (14.5).
When a non-player fighter goes up a level, the number of hp are increased by 1-10. However, when a player's fighter goes up a level, it is established that a '1' cannot be rolled by a player - so the increase to hp will be 2-10. Once again, this is intended to give players the edge.
These extra hit points that derive from class, or rather experience and training, should not be viewed as a layer of protection over top the combatant's BU. Rather, as the player grows in experience, the added hit points 'spread out' the biological units, in effect putting hit points between them. See the figure below:
In the example, the non-player character Yazina is first level. She has rolled 4 points for her BU mass and 3 points for her class hp, giving her a total of 7. Because she is classed, she has 10 hit points below zero instead of 4 (once again, see negative hit points). Because of that, the physical effect she would experience from being struck if she had no level is slightly mitigated by the few hit points she has gained through modest training (I say modest because she rolled poorly and only gained 3 hp, possibly from a poor roll or because she is a mage).
Whereas before, -1 hit point for a non-leveled combatant indicated a subdued illness (see above), now that is described by -1 to -3 hit points. Now -4 to -6 hit points indicates a serious illness and -7 to -9 a critical illness. Remember, it is at -4 that a leveled character has to roll to see if they are still conscious. Yazina gets these extra 6 hit points below zero because of her leveled training.
On the plus side, the three gained hp Yazina gained are all applied to vitality. Were she to get another level, the separation between her four points of BU (which do not increase with level!) would grow wider and wider. Any actual physical harm she received would only happen at the points where her BU was diminished, not her hit points. The damage that reduced her from 7 hit points to 6 would also reduce her BU from 4 to 3 - so a first attack against her would nick her arm or graze her face or leave a bruise. Another point of damage, dropping her total from 6 to 5, however, would not cause any physical effect.
None of this, at this time, is accounted for in game terms in my world, but interesting for the sake of role-playing (I do not expect players to keep track of this, it is theoretical knowledge that might apply if a character were to wonder if what they looked like after a battle). I am still considering how details like this may be made use of - for the time being, it is satisfying to understand what damage a combatant receives causes a physical effect and what only serves to lower a character's potential to go on fighting.
It is meant to be a change in thinking, not a change in the original game principles. Hit points and damage in the game remain largely unaltered by this change, so that no grand restructuring needs to be made to classes or existing monsters. It is added structure without needing to tear everything down and start again. For a more relaxed discussion of the rules suggested here, see my blog post BU to HP, particularly the comments below. Note that the blog post comments do not properly describe hit points lost to Wounds as written in this wiki.
See Attacking in Combat