BX Monsters A to Z: Djinni (Lesser)

 Turning now to Arabian and Middle-Eastern folklore, we find the djinni... or more specifically, the lesser djinni, whose name implies the existence of a greater djinni, which does not appear in B/X canon. Presumably the greater form was slated to appear in the never-realized Companion Set. (It did eventually turn up in Frank Mentzer's Companion Rules.)

A djinni (plural djinn) is described as an air elemental taking the form of a tall human-like being surrounded by clouds. It is highly magical, making saving throws at twice its actual level and immune to non-magical attacks. In purely physical terms, the djinni is a formidable opponent, with a respectable Armor Class of 5 and 7+1 Hit Dice (averaging about 32-33 hp if rolled honestly.) Its pummeling attack with its fists causes 2-16 points of damage, or twice that of a character with a normal sword. Its walking movement rate is a rather ho-hum 90'(30') but it can take to the air at a breezy 240'(80'). Adventuring parties would be well-advised not to pick a fight with a djinni unless they're sure they can defeat it, because its Morale score of 12 ensures it never gives up. 

Besides its physical abilities, djinn have seven magical abilities, each usable three times per day, apparently in keeping with the tradition of wishes coming in threes. The lesser djinni can't grant wishes, per se, but it can do some fairly impressive things which could potentially fit the bill in a limited capacity.

 It can create food and drink as a 7th-level cleric, so if you wish for a feast or for water in the desert, it's got you covered. 

It can create metallic objects of up to 1,000 coin (100 pound) weight, with duration depending on hardness (up to a fully day for gold, or as little as a single round for iron.) This ranges from potentially quite useful (and potentially very dishonest, if you plan to exchange temporary gold for real goods) to impressive but fairly pointless (a weapon or armor of iron or steel) to weirdly Bugs Bunny-esque (for instance, a 100-pound brass gong appearing suddenly in front of a fleeing thief, disappearing the next round and leaving the dazed thief lying in the street wondering what the hell just happened).

It can create soft goods including cloth and wooden objects of up to 1,000 coin weight and permanent duration. If you fancy a set of extravagant clothing, a luxurious tent, saddle and tack for a mount, a keg for water, a sail for a small boat, a long coil of rope, a wooden shield or weapon, fuel for a fire, or a plush divan, you're in luck.

It can become invisible, exceptionally useful if you need it to do some sneaking or spying for you.

It can assume gaseous form, good for making an escape, either for the creature itself or to pass through bars or keyholes to release its master from the other side.

It can create illusions that include sight and sound, which last until touched or dispelled and require no concentration to maintain. No other information is given, but it seems reasonable to apply the range and duration of the phantasmal force spell to this ability. If you need a quick mirage to fool or distract someone, this ability is hard to beat.

It can take the form of a whirlwind, 70' high by 20' wide at its top by 10' wide at its base, moving at 120'(40') and inflicting 2-12 points of damage to all creatures in its path. Creatures of less than 2 HD must make a saving throw vs. Death Ray or be swept aside. It's unclear what "swept aside" means in game terms, e.g. how far such creatures are moved, how long it takes them to right themselves afterward, etc. Whether character levels equate directly to Hit Dice for this purpose is also unspecified; personally I'd treat all humans and demi-humans as 1 HD, regardless of level. Interestingly, it takes five rounds to change from humanoid form to whirlwind or vice-versa, with no guidance at all as to whether this constitutes its only action for those five rounds or whether it can continue to use normal attacks or other abilities while it transforms. I'd lean toward the latter interpretation, else the creature would subject itself to five rounds of attacks unanswered every time it changed form. 

Finally, a djinni can carry up to 6,000 coins (600 pounds) tirelessly, or up to 12,000 for a limited time, making it an extremely valuable porter for those lucky enough to have one at their command.

Under normal circumstances, only one djinni is ever encountered at a time. It is listed as being Neutral in alignment. In folklore, djinn are often mischievous spirits, akin to how faeries are frequently depicted in European legend, but they can sometimes be bound to a mortal's will for some specific term of service. In popular tales, they inhabit magical oil lamps. In standard D&D, they can be called forth by a character wearing a ring of djinni summoning. No mention is made whether djinn are reliable in their service or will seek to make mischief while adhering to the exact wording of a command, but the Neutral alignment does suggest the creature will probably serve well if treated with respect, and twist words if treated disrespectfully.

 A character with a djinn at his or her service can draw on some very potent abilities, even if nowhere near as powerful as a wish proper. Despite its great versatility, however, a djinni under the control of an Expert-level party shouldn't be especially unbalancing, let alone game-breaking. A djinni in the service of an enemy or rival, though, can turn a mundane foe into a real challenge, forcing players to think and employ their own resources creatively.

Naturally, giving a djinni a distinctive personality would almost certainly increase the roleplaying fun of having one at the party's disposal or opposition. (No points for aping Robin Williams, though.)