I’ve been doing some research and running games and thinking a lot about hit points and damage as “timers” for combat and a way to gauge difficulty. The clear numbers in ICRPG makes it easy to think about since the formula for hit points and damage, etc. isn’t hidden behind some obscure math like DND. This has also been working it’s way into my attempts to add ICRPG procedures and play style into the White Box FMAG RPG.
In a 10 hit point world, like ICRPG, the d6 gives anything with 10 hit points a roughly three hit timer, (with average on a d6 being 3.5), give or take any modifiers. Level up to d8, d10, d12, and/or a critical hit damage roll, and you have a timer of one or two hits per 10 hit point participant (monster or PC). Keep your monster STAT and Effort bonuses in mind as well, because a monster/PC with +4 Effort doing Weapon damage can kill a one heart opponent in a single hit. Add a heart to a monster, and you add approximately three hits to the combat for each one, based on a d6 damage.
Additionally, your Target allows further refinement of difficulty by doing the d20 math (1 pip equals 5%). A Target of 10 is a 50/50 chance on an unmodified die, but a PC with +2 hits that 10 at 60% chance of success, needing only to roll an 8. I believe that is why Target 12 is called ultimate average in Master Edition, as PCs often have +2 or higher and rolling a 10 is 50/50. Target 15 is hard to hit and 18 makes the encounter very challenging, often needing natural rolls of 15 or higher to hit (30% chance to succeed).
The d20 and his little 5% faces are a great friend and easy way to think about how often a PC or monster will hit, and the 10 hit point heart allows you to consider the average of each die and consider how many of those will potentially kill a one heart target. We all know the dice are fickle creatures, so this is just a way to think about averages. There’s no way to wrap in the swing of a die, but it should be kept in mind. A flat d6 will never kill an undamaged one heart target, but rolling Ultimate for a crit, brings the average to 10, that’s a dead PC. Same with adding Effort bonuses or changing the damage die, you swing upwards each time.
I don’t strive for balance, I strive for fair and understandable encounters. If a monster is doing more than d6 damage, I let my players know that this monster is a meant to be a killer, and going recklessly into combat with it will have consequences. They are terrified of crits too and it’s awesome because they know what’s on the line when that d12 is going to roll.
Keep after it. The skill set builds with time at the table and with time reading and thinking about the math of the game. Read some other rules too to see how they are built and what they do with the hit point and damage “timers”.
