This is an introductory adventure for both Neoclassical Geek Revival and OSR retroclones. Everything in this adventure is dual-statted for both games.
I cannot comment on the NGR part of the book, but the OSR stats have a minimalistic elegance to them that actually makes this easy to run with pretty much any game. One of the enemy stats is listed simply as “3 hit dice, AC as leather, Attack as weapon, gore for 1d6.” While that may cause a beginning DM to feel confused and need to flip through books, those two lines give enough information that anyone who has memorized the basics of their game instantly fills in the blanks. It even works with non-D&D based games simply because of how stripped down the stats are.
The basic setting for A Thousand Dead Babies is an Earth-like town that recently converted to Christianity and the surrounding woods and fields. Lately, the town's priest has become scared of demon worshipers and witchcraft in the surrounding areas, and hires adventurers to investigate/eradicate.
There are a few different factions at work in the adventure. The townsfolk (mostly) follow the Holy Church, and want to see the old paganism driven from the land, a select few still follow the old pagan ways and want to see the new faith driven from the town, and there are evil demon worshipers who just want to watch the world burn. Depending on who lives, dies, or is skipped, it all spells out a different ending for the town. I like the sandbox-y nature of the adventure.
There is a small, totally optional, dungeon to explore as well. It is a mere six rooms, but contains interesting traps and dangers that change the outcome of the town and lands around it. There is one magic item that has almost no mechanical use, but will really affect the flavor of the adventure, and any to come after it. It would easily fit into a Lamentations of the Flame Princess module.
Zzarchov Kowolski adds in quite a bit of humor, and knows how to use tropes to his advantage. There are god-fearing townsfolk who want to drive all the other religions out and burn witches at the stake. You've got nature loving pagans who just want to protect their groves in the woods. There is a satanic cult that dances naked, sacrifices babies, with a stoic black knight and black goat presiding over it all. There is a threat of an inquisition incoming, and both the town and priest are rotten enough to be worried about it. There are a lot of cool things here, barely detailed, and just begging you to take them off in your own directions.
The art and layout for this book is gorgeous. Jez Gordon does the maps and a few interior illustrations, but even the page headers and the back cover's image imprinted as a watermark on the pages gives this an incredible sense of style. The stock art cover is the only color piece. While I normally do not really care much for stock art, it really fits the adventure in this case.
[4 of 5 Stars!]