Emberlight, a roguelike dungeon crawler from Quarter Onion Games is releasing with Linux support on August 13th and it does sound like it could be interesting.
Quarter Onion Games are saying it will be a "true roguelike dungeon crawler" and while they don't go on to explain what makes it "true" versus other games, I still love the sound of it. The gameplay loop in this especially, as you will absorb abilities used by enemies which eventually corrupts you. Eventually turning to darkness, you become the boss for the next run-through along with everything you provided them with.
Their trailer even has Linux mentioned very clearly at the end:
While I do love the sound of it, I'm curious to see how they will balance this corruption. If you always end up as the boss for the next run, can the game ever be won? That's a question I hope to find out at release. Apart from that, absorbing enemy abilities does sound very fun. Sound a little like MidBoss in a way, just without snatching their body too.
On Steam it currently only mentions Windows, so I spoke to the developer and they confirmed on Steam both Linux and Mac will be available at launch.
You can follow/wishlist it on Steam.
Remember: If you do wishlist things on Steam, set your platform properly to show up as a Linux wishlist.