In WH40k: Mechanicus you command a cohort of the Adeptus Mechanicus, your job is to investigate a Necron planet, and of course to deal with the threats.

The combat takes place on procedurally generated maps, it's kind of like XCOM, but with less RNG. You have your tech priests and their auxiliaries, basically use the latter the soak up damage and the former to shoot everything that moves. You can go melee, but the ranged options are just far-far superior. It can get a little easy (and samey) in later parts of the game.

Before you get to the combat you explore the necron tombs, chose your adventure style. The tricky part is the more you explore (and the longer the fights take), the faster the planet "wakes up", meaning the mission you are on and all subsequent ones will get harder. But the more you explore the more likely you'll have better equipment, and that makes your job easier. It's easy enough to manage.

On the campaign layer you advance the story, upgrade your stuff, and pick your next mission. You'll get options from several individuals, one wants you to explore and catalogue stuff in the tombs, the other to burn down everything, another wants you to get resources, yet another to help your pinned down troops. Their musings are hilarious.

Mechanicus oozes atmosphere. The writing, the visuals, the music, the "voice acting" of the high priests, all the little details show that a great care went into making this game. If you liked XCOM you will probably enjoy this one too.