Gelatinous Icosahedron

 In medieval times, they were architectural flourishes, placed on pillars and rooftops as silent guardians against evil spirits. In D&D, they tend to be evil themselves, or at least Chaotic and hostile. They're gargoyles, from the Basic Set. Protect your outdoor statue-monsters with Garg-Oil! From the makers of Min-Wax minotaur conditioner. Gargoyles are immediately stated to be magical monsters which save as Fighter:8. While that's a significant bit of information, it's far from the most interesting thing about them and the saving throw is readily evident in the stat block. It really seems as if Tom Moldvay struggled a lot in coming up with opening sentences for monster descriptions. Anyway... Gargoyles can be harmed only by magic or magical weapons, which right away makes them a serious threat to Basic-level characters. Like their real-world inspiration, they are described as horned, clawed, fanged, winged, and hideous, with skin that often looks exactly like stone, s

 It's always bothered me a little bit that falling damage in D&D is something that can be withstood by having more hit points. Sword blows, sure; hit points represent the skill and combat reflexes to turn potential killing strokes into glancing blows and superficial wounds. Arrows are a little trickier, but it's still possible to envision saving oneself from a shot to the heart with honed instincts and conditioned reflexes. Falling, though... gravity and inertia don't give a flying fork about how good a warrior you are. We all fall at 9.8 meters per second squared. There's a certain limit within which it's conceivable that a nimble and trained person can control his landing so as to distribute the force of impact to minimize injury, but if you're falling 50 feet, it's much less likely to make a difference whether you land gracefully or awkwardly. It's possible to model something a bit more "realistic" without abandoning the essential 1d6-pe

I thought I had posted this entry of B/X Monsters A to Z months ago, but I was just perusing my drafts, and there it was, clearly unpublished. So here it is now, hopefully better late than never. Just try to imagine it sandwiched between Efreeti and Elephant, where it should have been all along. I have to confess, I have never, ever used elementals in my D&D games. Was this a good choice or a poor one? Let's jump in and check these fellows out. Elementals are creatures made of one of the four classic elements: fire, water, air, or earth. Right off the bat, the description focuses on the summoning of elementals, noting that they can only be brought forth from a large quantity of the appropriate element, e.g. a bonfire, a pond or larger body of water, open air, or an expanse of bare earth or stone, respectively. It is also noted that a summoned elemental must be controlled by its summoner to the exclusion of all else: the summoner cannot move faster than half speed, take any dama

 Combat offense in D&D is modeled with attack rolls, using d20, modified by class and level plus ability score modifiers or by creature Hit Dice, in either case representing some combination of skill and physical power, and by a damage roll, generally representing the amount of force brought to bear on a successful attack. It can be a wonky system, and sometimes counter to our intuitions of how combat and bodily injury actually work, but it serves its purpose well enough in the game. Defense in D&D combat can be even wonkier and less intuitively satisfying. Like offense, it's broken down into two primary components, Armor Class and hit points. Both, conceptually, serve the same broad function, which is to represent the avoidance or reduction in severity of bodily injury, but they do so in ways which are mathematically distinct and very different intuitively.  Armor Class is the more intuitively comprehensible of the two, though it itself represents two semi-distinct concept

 For most of my D&D-playing life, I've given very little thought to the Treasure Type tables. You just roll the percentile dice against a creature's listed type and cobble together its treasure hoard, and that's that. Easy-peasy. I never considered whether or not there were reasons behind those numbers in the table, why some types had larger or smaller chances for larger or smaller amounts of particular kinds of coins, why so many entries in the table were "Nil," or why some seemed not to be used at all. If tedious minutiae are your jam, then join me now on a deep dive into the B/X Treasure Type tables! The first thing I did in my analysis was to calculate the average value of each Treasure Type. I had finished this step before I realized the books provide average values already, and I'm glad I did, because the book values seem a bit... wonky. Some of them are right in the same ballpark as my calculations, and could simply be the result of different roundi

 No fish stories here; these monstrous swimmers really are found in the D&D Expert Rules set. Four varieties of giant fish are described: piranha, rockfish, catfish, and sturgeon. (It's interesting to note that B/X's successor, the Mentzer/BECMI Expert Rules set, lists three kinds, doing away with the piranha and catfish and adding the giant bass.) Giant Piranha : Much bigger versions of the classic Amazon River terrors, these piranhas are around five feet long and have a respectable AC 6 and 3+3 Hit Dice, placing them above the average warhorse in toughness. From 2-8 of these fish will be encountered. They will attack any disturbance in the water near them, and up to eight can attack a single man-sized target at once, dealing out 1-8 points of damage with each successful attack. Morale is listed as 7, but once blood is drawn, they go into a frenzy and no longer check morale. Piranha are found in warm freshwater, rivers or occasionally lakes. Giant Rockfish : Denizens of sh