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I'm looking for a book series I started but never finished 20+ years ago. It was about a group of colonists who ended up on an inhabited planet. Some, maybe all, of the characters were sent there as punishment for crimes. The main character's name was Cord, he was really strong. The villain's name was Lamprey, he was violent and had been in some kind of special ops military group back on Earth.
The native inhabitants of the planet were peaceful and not particularly dangerous, if I recall correctly.
Looking for this on Google has taught me much I didn't know about the spinal cords of lampreys and other fish, but no luck finding the book I'm after.