Wow, that's a lot to digest and discuss!
I guess first I need to explicitly say that it's really hard to evaluate how the game would feel without actually playing it with the changes, so my ramblings are highly theoretical. I see two things in your plan that I would mark as risks:
- The change I fear the most is the introduction of the Wound (and similar) cards. If I recall correctly, during my playthrough I got beaten quite a lot (especially when I became longer and had someone chasing my tail), so I would end up with tons of these Wound cards. I assume you do intend to allow removing Wounds from the deck (as opposed to the hand) somehow - otherwise the following is exacerbated even further.
- I fear the situation where I accumulate a lot of wounds, but don't have a healing effect (terrain, card, whatever), and I just end up redrawing wounds endlessly - this doesn't feel like a lot of fun.
- I also imagine myself circling across mushroom terrain endlessly because I need to heal all those wounds - again, not super fun.
- That said, perhaps optimizing for not getting hit will turn out natural, or balancing of healing items and terrains will minimize the chances of this happening.
- That said, I haven't played Slay the Spire (yeah I know, I'm weird), so maybe I'm not visualizing the mechanic too well
- While in my runs I only ever died of starvation, I do remember keeping an eye out on my HP, and I kinda enjoyed that I needed to balance two resources (HP and energy). More importantly, I needed to choose cards with HP (and poison!) in mind, so it definitely affected my strategy a lot. On the flip side, it might have affected my strategy too much, because not having a healing card when you meet Trained Slimes is near suicide. Removing the Wyrm HP altogether indeed turns it into a very different game - and there is a risk that you'd lose something fun (not that you can't revert if that turns out to be the case).
Regarding the enemy HP- I indeed have not noticed the enemies having armor (although I did know that they don't always die in one hit). Was there some kind of indicator of the enemy's armor and remaining HP? I think having just a single hitpoint (and no armor) on the enemies might be a better design because it removes all the complication of tracking these things (for the player more so than the dev). Although I see how this removes some cards from the pool (Strengthen, the cards about tail-adjacent damage and body-adjacent damage becoming identical, etc.), so maybe it just removes too much?
> I'll add some Slime/Crystal/Mushroom walls that when dug out, leave a consumable slime/crystal/mushroom
That sounds like a great change - not finding the stairs is sometimes frustrating if you feel like you didn't waste THAT much time on the level. I also wonder if it's possible to add a way to scroll the map off-center to see the rest of the level (you might remember that even in zoomed-out mode I still couldn't) - although one could argue that remembering the map is a skill, it's not a skill I personally find particularly fun :)
> You're the only person I know of other than myself to make it past level 2.
That's interesting - I actually reached level 3 several times (prior to the video), so that did not feel like a problem to me.
> new suit of Lava enemies, cards, and terrain ;)
The 4th tribe :exploding head:
One last thing I want to note is probably something you understand without my feedback, but good to explicitly call out regardless. In my playthrough, some cards felt next to useless, and mobility cards felt really powerful. While this will get shaken up quite a bit with all the changes you plan, the core challenge would remain: you want to offer a set of cards that are balanced in a way that every card could be viable in some build - and there should be several viable builds. Furthermore, ideally the builds should be a reaction to the game state, as opposed to just something a player can determine ahead of time and stick to. In the current version of the game, I did not get an impression that I was adapting to the game state as much as just picking what I believed "globally" best. I mean, I like the game without all of this, but if it had this quality, it would be even more replayable and deep!