I really loved this game! The visuals were, of course, stunning especially the tums, but I also liked the conceit of of the combat system, where enemies can be defeated through brute strength but also through experimentation, finding the fastest and most efficient way to get them stunned. I will note, however, that the optimal solution to many enemies, particularly in tier 4, was to stun them and then pat them for a 30 seconds to a minute in order to recoup lost health. This slowed down combat a great deal, and overall made for a not terribly fun tier 4, despite the enemy and map design being especially good in that area. I might recommend limiting 'pat' so that the optimal approach no longer takes a long time, or creating a more powerful action that drains the health of stunned enemies only, in order to speed up combat without actually changing the difficulty. Additionally, I think a cut-scene viewer from the main menu or from the room would be both a great QOL update, both to prevent having to refight the dark queen to look at an ending again, and to track completion.
Overall, I found this to be a remarkably polished game, not just for a small, admittedly niche audience, but also for any indie RPG-Maker game. The UI and art-style were cohesive, appealing, and simple, without any unnecessary noise or unnecessarily specific inventory categories. As a final note, I really enjoyed both 9 Months and Overnight, but this is an enormous step up in both scope and quality. I seriously recommend you keep making games, HellBrains! They have, this one especially, something special and hard to find!