Hellslave is a dark fantasy dungeon crawler where you make a pact with the Devil to fight back a demon invasion. It's free to keep if you're quick. They've recently announced a sequel, so this is one way to get people interested in it and get some wishlists.
It has some quite lovely artwork to it, check out the trailer:

Direct Link
Game Features:
Fight Fierce Enemies and Overcome Nightmarish Bosses - Deal with dozens of enemies from reanimated zombies, ghastly ghosts, and hellish demons. Confront monstrous bosses that could be the end of you or your salvation.
Unleash Powerful Demonic Abilities - Customize your character with a unique passive skill tree, and experiment with dozens of demonic powers. Master the art of synergy, create devastating combos that crush your enemies.
Explore a Dark and Dangerous World - Travel on world maps filled with dozens of unique landmarks but beware of what lurks in the dark. From villages to graveyards and crypts, destroy your foes, retrieve old relics to help the inhabitants of this doomed world.
Immerse Yourself in Dark Fantasy Art - Every moment of your journey is brought to life with stunning hand-crafted visuals and atmospheric cutscenes. Immerse yourself in a world where beauty and horror coexist, inspired by dark fantasy literature and art.
New Game+ for Endless Replays - The demons may have been defeated, but Hellslave is never the same twice. Unlock New Game+ and replay the nightmare with increased difficulty, different starting demons, and new challenges awaiting at every turn.
A Dark Fantasy Experience Like No Other - Hellslave brings classic dungeon crawling to life in a new, twisted form. Drawing inspiration from dark fantasy literature and artists like John Milton, it combines brutal turn-based combat, strategic gameplay, and a gripping story that will keep you on the edge.
It's rated Playable for Steam Deck / SteamOS, and has a Platinum rating on ProtonDB.
Free to claim and keep. You just have to add it to your Steam account before June 16 at 5PM UTC.