Did you think that ravening monsters and evil wizards were the main threats against your character's life and well-being? Think again!
This book aims to give the DM a range of natural ways of making characters ill - the sorts of 'real world' dangers that threaten anyone, particularly in the average mediaeval-style setting of most D&D games. Each is provided with game information in the shape of Fortitude saves to avoid or minimise the effects, and a range of effects over and above mere attribute loss, designed to enhance role-playing and realism.
The first chapter looks at plant-based poisons. While many could be used by an evil herbalist or assassin, the emphasis is on accidental poisoning - eating the wrong mushroom or a dodgy piece of shellfish - rather than deliberate attempts to do away with someone. The effects are bad enough to make anyone want to think twice about what they are just about to eat. It's good to see the linkage between 'game effects' such as hit point and attribute loss and negative circumstance modifiers, and more descriptive effects such as suffering stomach cramps or extreme thirst. The tools are there for those who want to role-play the difficulties that their characters are in.
The second chapter gives the same treatment to diseases - how easy and under what conditions you might catch them, what the effects are and how (if) you'll get better. There are also some variants on the standard D&D rules for curing diseases by spell - so that those DMs who want to make use of diseases will not see them waved out of existence by a cleric's hand! These new rules are well-thought out and still give characters a good chance of survival without making it a certainty, or enabling them to bypass all the ill effects.
This is a book to be used with caution. It would be all too easy to just fill your world with poisonous plants and nasty illnesses, and end up with characters too feeble to wave a sword or cast a spell. But used with care, it can add an extra layer of realism to your game world.