AD&D Version 2.6 is based upon the role an average 0-level human has in the game environment - as explained in the Player’s Hand Book. Accordingly, 0-level human populations serve as the foundation upon which the more fantastic elements of the game are juxtaposed. To the average human, monsters of 2 Hit Dice, such as Gnolls, should be menacing indeed. Characters of high HD should be seen as relatively formidable individuals if their deeds are witnessed or recognized.
Since the original Dungeons and Dragons game, created in the 1970s, was derived from army-sized wargaming, using 0-level soldiers, the game was built upon this perspective. It was assumed Player Character parties would be large (safety in numbers) in a NPC rich environment. Henchmen and Hirelings were supposed to be an integral part of the game - hence the details and rules provided for them in the core rule books. This sort of mindset would have made lower level gaming more survivable, although character survival was still a challenge.
In First Edition AD&D there was a focus on what one might consider low or medium level campaigning. Characters of 9th or 10th level were considered to be at "name level", where the rule books provided information on strongholds or hideouts. At this stage the character would be in charge of various retainers or followers and be one of the most powerful individuals in the land. There was an implicit assumption they were semi-retired, and at the highest levels of their power. These sorts of limits are reflected in many of the toughest monsters, like Vampires, or even Demons, that had hit dice near the 10 HD mark.
0-level Character rules
The following optional rules serve as a guideline for the introduction of more multi-dimensional 0-level humans (or demi-humans):
*Non-weapon Proficiencies: 0-level humans may have any number of relevant non-weapon proficiencies depending on their profession & background (at the DM’s discretion).
*Weapon Proficiencies: Certain 0-level characters may receive 1 or 2 weapon proficiencies. These can be assigned to particular weapons or tools with which they have familiarity. Penalties for using weapons in which they have no proficiency give a –4 to hit for an unfamiliar-type weapon, and –2 for weapons of a similar form to their proficiency. Characters who are non-proficient in the use of missile weapons fire at a rate one lower than normal i.e. The ROF from a short bow would be 3/2 instead of 2/1 (or 1/1 for 3/2 if that DM option is being used - see Combat).
*0-level humans may receive bonus hit points, or bonuses to their initial constitution scores, at the discretion of the DM. An active and experienced woodcutter, or blacksmith, may have the stamina and wit to sustain themselves in a fight, and so may have one or two additional Hit Dice, along with any constitution bonus. Other 0-level NPCs, such as active alchemists or sages, may have bonuses to their original hit points, adding +1hp or +2hp 'per level' (not whole HD) depending on their activities. Whether they should also include a constitution bonus to these additional hit point is up to the DM. Unlike adventuring types, or thieves, the infrequent forays of these 0-level NPCs into danger, preclude advancement as a true character class.
*0-level characters with improved hit points may have an improved THACO which only advances very slightly, due to their lack of combat experience. Weapons in which they have trained, or used constantly, such as a blacksmith's hammer, should receive bonuses to hit.
*Key 0-level characters, that join with adventuring bands, may be trained to become a character class, but they require time spent in specific training and also need higher than normal prime requisite numbers in order to make this change. However, such characters will end up as Henchmen, and have a penalty of only receiving 50% experience points per encounter. Furthermore, no extra hit points are gained until the character has passed their previous accumulated HD and/or bonus hit points 'per level' (counting any +1hp or +2hp 'per level' as HD levels).
*Some 0-level humans may be eligible candidates to learn minor magics or receive spell-like powers at the DM’s discretion.
*The DM can rule that 0-level characters (and low HD monsters) that fall below 0hp suffer similarly to PCs in the same predicament. A final negative score of -6 is a recommendation.
*Combat tactics for 0-level individuals include safety in numbers, the use of ad hoc shield walls, spears, guard dogs, plus missile fire, with the strong inclination to retreat or run away from danger when facing overwhelming opposition.