Perhaps eight thousand years ago, a people now forgotten built a massive juggernaut. It was a moving fortress, a war machine built to lay waste to everything in its path, and they sent it against their no-longer-remembered foe, crushing towns and reducing even the mightiest fortifications to rubble; for the war was not about conquering, but about destroying the enemy.
While passing through a valley, the beleaguered enemy surrounded and boarded the juggernaut and slaughtered the army within. The enchantments used to create the juggernaut were so powerful that its hull could not be destroyed, but the victors did what they could with hammers, axes and fire to ensure it would never be used again. Its weapons they removed and broke into pieces, which they scattered across the Flanaess. They buried what they could not destroy, leaving only a
windrmll-shaped stone structure above Oerth’s surface, a monument to their triumph

From: The Doomgrinder Adventure Module Introduction.

This was one of my favorite early adventures (although I had been playing for almost 15 years by the time my group played it) We didn't do a lot of commercial adventures but this one was too cool not to run (plus it offered the opportunity to "burn in" some new characters and enjoy the general chaos of a giant war machine rolling through downtown Greyhawk.) The original maps were very well done in a hand drawn style by Sam Wood. I'm going to go for a more "realistic" style while still (hopefully) paying homage to the original. This is one of my collection of early adventures that I was lucky enough to purchase from a out of business hobby store about 10 years ago. The owner had boxes and boxes of dust covered modules of all sorts and just wanted them gone so he could sell his building. Needless to say I got a great deal. This first map is a very preliminary version of the Engine Room of the Doomgrinder. I will probably end up doing the actual engine and driveshaft in Sketchup as I'm pretty sure it would just look like a couple of rectangles with two lines sticking out of them otherwise. (it still might we'll see.) The triangle shaped empty spaces in the walls are arrow slits.

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