There have been 40,000 Warhammer 40,000 video games, but none I'm aware of revolve around the Adeptus Mechanicus.
The Adeptus Mechanicus are a group of humans who really, really love steel, technology and machines. They live on Mars building the Imperium's tech, while maintaining an army of their own. Basically, if Digital Foundry was a Warhammer 40,000 race, it would be The Adeptus Mechanicus.
So we come to Warhammer 40,000: Mechanicus, a new game published by Kasedo Games (Rise of Industry) and developed by little-known French studio Bulwark (Crowntakers). There's not much to go on right now, but we do know Mechanicus is a turn-based tactical game set for release on PC, Mac and Linux later this year. I'm hoping for an XCOM-style game, basically. Here are some pre-alpha screenshots:
You control Magos Dominus Faustinius and lead the expedition on the newly rediscovered planet of Silva Tenebris. Here's the official blurb:
You can upgrade your troops with augments and replace their limbs with bionics "made from the blessed metals of the Omnissiah". The story was written by Black Library author Ben Counter.
The teaser trailer doesn't tell us much of anything about the game, either, but it really nails the Mechanicus vibe with a super cool voice over depicting the recording of a deceased Tech-Priest, Magos Dominus Reditus. It's certainly worth a watch if you're into Warhammer 40,000.
It's hard to make a call on this one until gameplay footage is released, but colour me intrigued.