Pedants. We all occasionally have to deal with them, especially in this hobby. Just go browse an OSR forum and you'll find plenty of them, all itching to show off their "733t DnD skillz, boy." There are two types and both are bad.
First, the more annoying of the two is the player pedant. This is the chap who has memorized all of the pre-1985 OD&D, D&D, and AD&D rule books, down to footnotes and obscure references. I'm not sure which is more annoying: the type of player pedant who is a rule lawyer looking for the best angle for his character (and his alone, never the party) or the one who bogs down the game disputing with the DM just because he knows more than the DM. This is definitely not a face you want to see looking at you from the other side of the screen.
For the DM, beware of this creature. He can make the game a living Hell and make the players start to leave in droves. The true pedant will do it by slowing the game to a crawl as he disputes, for 30 minutes, a ruling on one segment of the combat. And I'm not talking about an attack that would kill his player. No, I'm talking about a 1 hp hit by a party NPC on a goblin. He'll do this just because "I'm right!" and he wants to prove his superior knowledge of all things Gygaxian. Sadly, this is the type that also has zero social skills, and the only solution is to eject him from the game.
The rules lawyer, on the other hand, can usually be redeemed. He just wants to win the game. Squash him as needed and prove your superior rulesmanship and he'll give you grudging respect, sort of like Brian in KoDT. Many of these types actually have quick minds and good imagination. With the proper training, they usually make good DMs.
The referee pedant, on the other suffers from a different malady. This is the type who loves to drag out combat and make it more "realistic" (i.e., deadly) for the party. Miniatures, detailed sets, speed factor, weapon vs. AC adjustments...the whole shebang. Or he could be the type that has a full page of flavor text FOR EACH ROOM IN THE DUNGEON. The danger for the PCs with this type of DM is to for the characters to survive the battle and for the player to avoid falling asleep. Hmmm, maybe that's his gameplan: to make the players so sleepy that they are unable to think tactically....
The best advice for this guy is to tone it the Hell down. Don't neglect to mention the ogre standing in the middle of the room, but don't tell the players (in excruciating detail!) about the fine detail of the bas relief in the room, inch by bloody inch.
With today's monster, we get back to one of the more deadly and alien types.
AC: 5  Special: Immune to mental attacks, fire resistant
HD: 4 Move: 4
Attacks: Infection HDE/XP: 7/120
This creauture is believed by many sages to have an otherworldly, or even extraplanar, origin. It appears as a disgusting blob and pile of rotting matter covered in capped fungi and exuding a milky substance that allows it to creep along at a slow pace. A phycomid is immune to all mental attacks (sleep, charm, etc.) and gains a +4 to save vs. fire-based attacks. To attack, it extends a tube-like appendage and launches a globule of a highly alkaline fluid at up to 2 different target with a range of 12 feet. This spittle only causes 1d6 damage; however, if the victim fails a save, he takes an additional 1d6+2 damage and begins to sprout mushroom-like growth at the infected area. This growth (and damage) will occur in 1d6+2 rounds; the growths will begin to spread across the victim's body and will kill him in another 1d6+2 rounds unless a cure disease spell is cast. If the victim is killed, he becomes a new phycomid.