First spotted by AlphaBetaGamer, Van Hellswing's free demo already gets my hearty recommendation. It's basically like Devil Daggers—horde mode PFS survival against floating, swarming enemies—except you're trapped in a vertically complex arena and given a sick grappling hook.
That movement's really the star of the show here. Despite the name, Van Hellswing's signature move is more of a Zelda hookshot deal than a Titanfall, Spiderman swing one, but it's a joy to use. It caps off a moveset that also includes a double jump, dash, wall run, and bunnyhopping, and developer Codeclue has really made the perfect bedrock for almost any kind of shooter they wanted, not just a survival arena.
Your sole weapon is a double barrel flintlock, which you use to take out swarming, homing bats that grow in strength and number as time goes on. If I have one mechanical complaint, it's that there isn't really a clear enough screenshake or knockback to indicate when you're taking damage—enemies kind of just bump into you and all of a sudden your screen's getting all these red spiderwebbing cracks, and I often found my deaths in the demo to be abrupt and frustrating.
Otherwise though, Van Hellswing's prototype is a perfect little bite-sized shooter. I managed a high score of around 20k in my best run tooling around the game so far, while the best I've seen shared by the game's official Twitter account are north of 70,000. Developer Codeglue seems keen on expanding the concept in the future, and you can check out the demo yourself on itch.io.