Initial scrolling of the Steam Summer Sale seems pretty lackluster, but digging through the comments sections in other threads, a few gems have stood out, and it doesn't appear we have a thread dedicated to this yet, so post what you think are the best deals here!
Not mandatory ofc, but it'd be helpful if...
One game per top level post, so comments stemming from it are focused on on just it.
Include a short blurb about the game - if it's one you've played before, what did you like about it? If you're diving in blind, what grabbed your attention?
It's a turn-based traditional roguelike + dungeon crawler, i.e. there are no in-game permanent upgrades to make the characters stronger, and only you the player get "stronger" as you become more knowledgeable. If you are into that kind of game, this is absolutely one of the best I've played!
The developer Evan has been continuously updating the game for the past decade, with a new, sixth playable hero scheduled to release later this year. The game is also free and open source, so you can even play the full game for free. I bought the Steam version (and has sunk 100+ hrs into it) because it's so rare for me nowadays to find a game I don't get tired of after a handful of hours. (Not saying short games are necessarily bad though, some of my faves are very short too.)