I love a good dungeon-crawler. I really like the simple look of the ruins, it made it feel like one of those old retro computer games I played when I was a kid. And the lighting was dark enough that I felt a bit on-edge at all times. I thought the platforming was an interesting choice but I had a lot of difficulty with scaling the ledges; sometimes it was incredibly finicky and wouldn't climb up unless I was dead-center on the ledge. And even though I'm used to Shift and Space being the 'run' and 'jump' buttons on a ton of games, I wasn't able to get it so that I could dash and jump at the same time. I had to finagle my way around some of the longer jumps to progress at a few points.
I think one huge thing that would help players is a map of some kind so that they know where they're going. The areas can get pretty confusing at a few points, and I was turned around fairly often when I thought I was going one way and ended up in a room I'd already been in.
Overall, this is a fun entry to play. Thank you for making this.