Into the Odd x Darkest Dungeon

I doubt this is unprecedented, but talking to a good friend about Darkest Dungeon's Death's Door mechanic opened the perfect door to solve a self-imposed problem: how do I succinctly explain taking damage in Into the Odd?

For background, Darkest Dungeon has its characters as fine being attacked (more or less) until their HP hits 0, at which point they are at Death's Door. Once they are in this state, any attack targeting them has a chance to kill them - specifically equal to their Death Blow resistance (i.e. their Death Save) - and it is only in this state that they are susceptible to death.

Now, I've been struggling to articulate Into the Odd's damage procedure to my inexperienced players... or at least it has never come easy to me. The whole reason I created my own homebrew document was that I was terrible at explaining the rules to my players, and needed to organize my thoughts/give them an easy-to-use reference. 

While most of the rules came across fine, I spent almost half a page laying out the procedure for dealing/taking damage. Even after half a year of rewording and remixing the rules to fit all sorts of worlds and mechanics, I still haven't found a satisfying way to write down the procedure - though I feel closer now more than ever.

There is one last piece of context: as a math major and long-time tutor, I know the importance of minimizing cognitive load when doing repetitive math. As such, I ascribe to the Target20 paradigm of adding rather than subtracting whenever possible in any mental arithmetic. So, when I was trying to implement something like a Death's Door state in Into the Odd I arrived at the following:

• Reduce incoming Damage by AP if any, then add it to cumulative Harm
• If Harm is equal to or over max Harm Protection, the character becomes Vulnerable
• Once Vulnerable, further Damage is recorded, triggering a Damage Save vs Critical
• If cumulative Damage is equal to or over max Strength, the character is Dead

Though the details of each step can be better written and explored, I find this procedure to be clearly more to my taste. Gone is tracking any HP subtraction and stat loss, and replacing it is addition and comparison - two of the easiest mathematical operations. 

The procedure also retains the dissociation of landing a hit and confirming the critical which I prefer, while maintaining the ludo-narrative structure of violence in Into the Odd which fits my approach to combat. For example, writing what I consider Combat Maneuvers becomes much simpler: resolve it with the most at risk making a Save; if it would directly remove the target from combat, it is only possible if the target is Vulnerable.