There have been plenty of well-known hardcore bands from Michigan, such as Negative Approach, Necros, The Meatmen, Pittbull and Earthmover. A lesser known one is Hyde. Hyde were around from around the turn of the century till 2002 or so and they were a band that was quite metal while still rooted in hardcore. They mixed thrash metal with hardcore, and it ended up being an awesome mix. Here's their 'Separate Yourself From Existence' demo from 2000. They would release a MCD called 'The Sky's False Persona' on Tribunal Records later that year. In 2002 they would release another album on Tribunal Records, called 'A Beautiful Nightmare', for which they re-recorded 2 of the these demo-tracks. That was the last release of theirs I'm aware of. I can recommend both releases, and 'A Beautiful Nightmare' can still be picked up for a mere $.99 from the Tribunal estore. Members moved on to The Alliance and Poison Tongues who I wrote about here. Enjoy!
Hyde - Separate Yourself From Existence demo