First of all, thank you so much for taking the time to play and write an in-depth comment!
Regarding the lower spec computer, yeah, there might be some limitations and/or performance issues on weaker machines, I didn't get to test on a weak computer. I might need to optimize a lot in the future to solve that.
Thanks for the comments about the UI, it still needs work but it is getting there.
I'm a solodev, so while I do plan on releasing it commercially if I get the game to a passable enough state, I don't know if it could be considered a "commercial project" just yet.
Tutorials will be coming at some point, and I know it is very necessary, I just haven't gotten around to giving newer players a nice explanation of all the complicated mechanics.
I'm glad you liked the hover to explain keywords mechanic because I kinda just made that from scratch on the same day the demo released so the fact it works as well as it does it's a miracle.
I didn't know about this spell checker, thank you very much for the link I'll look into it!
You start at 1 mana and get 1 mana per turn, so it's simplified from the MTG land system.
Changing the UI for the mana is on the plans, yeah. I'll make it into something more intuitive.
I gave up on implementing multiplayer because this was a learning project and the resulting code is a bit too whack. Sorry :c.
The music will almost completely be replaced and improved on in future iterations.
You don't have to press C you can also click the inventory button on top, so you can play with only the mouse.
I've received this sort of feedback before, so yeah, I'm already working on adding something more obvious to show your card is exhausted.
First couple of combats will be slightly rebalanced to make it less tedious, that's also already in the plans.
The crafting will be replaced with a way more user friendly, the bug with piercing might be a thing or maybe you just didn't click the confirm arrow for that ability, I'll test that out. Also regarding skipping the second active, that's because Minions can only have 1 active, if you create spells you can use both actives. Also it looks a bit overpowered, but the game gets harder as you progress so the idea is that you kinda need the OP cards. And yeah, rewinding would be hard to implement, and since I'm eventually going to replace the way you craft entirely, I just didn't spend time doing that.
You can't change the type of card or image you are creating, but I'll keep your comment in mind!
Healing potions are great for other classes or for saving your ass against hard enemies since you can use them in battle.
The event history might be hard to implement, but I have thought about adding it, yeah.
The last part is in fact a bug, I thought shit had been resolved already but looks like it hasn't, so I'll keep working on it.
Castle raid does have a "save and then pick back up" feature, if you quick or die the run is over. Eventually I'll allow the player to continue the game but there's no saving at the moment. The load button is reserved for the other mode.