Northworld is a collection of three David Drake novels. Each takes place in the 'Northworld' - a set of eight interlinked planets, connected via an interdimensional soup called the 'Matrix'. Nils Hansen is a supercop for the Universal Consortium of Planets (or whatever). After previous attempts to figure out Northworld failed, Hansen is sent solo to see the sights.
In the course of all three books, Hansen explores the various aspects of the Northworld - including the lizard plane, the dinosaur plane, the plane filled with sentient computers and the plane populated solely by depressed fungus. Most of these explorations, however, are merely cursory.
The majority of Hansen's time in all three novels is spent in the Open Lands, a generic medieval world filled with by-the-book feudal types, waving around swords and doing their damndest to expand to the village next-door. The one twist is the introduction of power suits - incredibly high-tech battle armor (think Iron Man with a lightsaber). This adds a particularly lethal twist to the medieval shenanigans.
The fighting is, without a doubt, a hoot. Drake carefully describes the stench and smell of battle in every piece of minute detail. For a fantastic construct, the powersuit is incredibly well-described, and by the end of Northworld: Vengeance, I'm pretty sure I could build one myself. Less attention is paid to the rest of Open Lands (or even Northworld) society - Hansen doesn't seem to care and Drake is happy to keep his main character as incurious as possible.
As much fun as it is to read about armored men blowing up buildings ("ARC!" -kablooie-), the three novels are each built around a premise that is invariably, and repeatedly, proven false. Hansen is constantly introduced as the bee's knees because of his knowledge of tactics and strategy. He's an impressive trainer, and his ability to lead his troops successfully is always shown to be in stark contrast to the other feudal warriors. The thing is, in Northworld, this doesn't really matter. Although strategy is grand, the biggest gun always wins.
All three books have the same plot. For some reason or another, Hansen is dropped into the Open Lands. He scrounges up a crappy powered suit and invents a new tactic (book 1, where he invents 'teamwork' is particularly imaginative) that impresses a local warlord. They beat up some other locals, then get smacked about by a Big Evil Empire that has better powersuits. Hansen is doomed - utterly - until some twist of fate gives him a the best powersuit of all. With the new ubersuit, he wins the day. Kablooie.
Repeated three times, this gets a little old.
There are other plots mixed in, as Drake likes to show off how manly Hansen is in a variety of ways. Occasionally, in-between fighting in his powersuit, Hansen will pop over into other dimensions and strangle lizards. Or blow up a cavern filled with post-apocalyptic railgun-wielding evil mutants. Etc. Mostly though, this is filler. The real fun is in the Open Lands.
There are no characters worth mentioning (this includes Hansen, who has the personality of a sock filled with bricks) - the heroes are the suits themselves, who continually steal the show. Which, of course, leads to the final question - what's going on with the cover to this book? The most lethal science-fiction military technology since Heinlein, and... it looks like this?
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