Just How Dangerous Is Combat?

    A question for you dear reader: how many hits does it take to kill someone on average (both median and mean) in Pathfinder?
    If you're like me, odds are you never really thought about it much.  "Not many" at the lower levels to "a whole lot" at the higher levels might be your reply.  While combat starts very deadly it seems to take a million swings-and-misses by the teens, and ironically very deadly again at the highest levels with all the save-or-die effects.
    You also might be asking, so what?  Well, as both player and GM it is very important to know how deadly combat is, because you need to know what is effective.  Let's say weapons only do 1 HP of damage per hit.  Imagine this: two fighters circle, looking for an opening, and they only have 1 HP each - so the first hit will be the last.  Let's look at another example: two demigods circle, looking for an opening, each has 1,000,000,000 HP - so it's going to take a whole lot of hits to end the fight.  In the first case, with only 1 hit to kill, getting that hit becomes all-important.  You would want to take Improved Initiative for sure, and a really high Dex, to make sure you get off that first shot (and it lands).  But with a billion hits to kill, well, that's a more leisurely pace.  You have breathing room, you can try different combat maneuvers and options, since even if you fail and get hit in return, well, no big deal - lots more HP where that came from.  A low hit to kill system has a different focus from a high hit to kill one.  And as a GM, you never want to put the one HP opponent against the billion HP opponent, the lower side has no chance at all of winning, and is going to be a boring fight (well, unless you make it a very bad idea to kill the lower side, but that's another post).
    In our Pathfinder example, at low levels you pick fights very carefully, even bypass them when possible, because combat is deadly.  But by the teens you are wading into the middle of a horde of goblins, slaying them with gay abandon.  At the higher levels you stop worrying so much about armor class and start taking a hard look at your saves.  The different pacing leads to different priorities and behavior.
    But while knowing the hits to kill of Pathfinder is nice, again it is kind of unimportant - well, let's say once you know it you don't really have to think about it.  But there is a time when you have to think a lot about how dangerous your game's combat system is: when you switch to playing another game.

    If you've read the blog you know I've been making house rules for 13th Age, and digging into the structure of the system in some depth.  I started by looking at how the abilities worked, and then moved on to spells, since I want to make sure the house rules I created work within the framework of the game.  As a part of that, I have had to look at spells - specifically how spell damage compares to weapon damage.  From there I ended up taking apart the whole combat system.  And what I found explained something about the system I had felt but been unable to articulate.
    There is sort of a staple in D&D gaming, the goblin.  Virtually every 1st level player will fight the 1st level goblin as a beginning step on the road to bigger and better monsters.  When we ended our Pathfinder campaign and started the 13th Age one, I decided to keep the tradition alive and so the first encounter was between my 4 characters (my 2 friends, me as both GM and player, and the Bear animal companion who I upgraded to 1st level instead of the book 0th level) and 4 goblins.  From my Pathfinder experience I thought this would be a somewhat challenging but predictable win for the party.  Instead the bear went down and everybody was injured and glad to be alive at the end.  Which was when I noticed something, 13th Age combat is a lot more deadly than Pathfinder's was.  But until I pulled apart the numbers, I didn't really know why.  What I did know was that I was going to have to be careful, I've put in fewer monsters and played them kind of dumb (and fudged more than a few dice rolls, my players were just as surprised as me, so I didn't want to punish them for not knowing a system that I couldn't prepare them for).
    The thing is, every game is built on assumptions.  How hard should the players be compared to the monsters, how many hits should an average fight last, what options are available to both sides and how often can they use them and how big an impact do they have?  These are all decisions made by the game designers and usually hidden under all the numbers and feats and attributes and progressions and stuff that makes it hard to see the forest for the trees.
    Let's look at Pathfinder again.  The default attack in Pathfinder is the naked man.  A naked man has a base armor class of 10.  With no other modifiers, the base attacker has a zero modifier and a d20 roll.  You have to roll over, so the odds of rolling 11 - 20 is 50%.  So all attacks, at the most basic level, have a 50% to hit.  Armor and Dex make that lower for the defender, BAB progression and Str make that higher for the attacker, and there are a millions feats and spells that can change that equation.
    Okay, so once we hit, how many hits to kill?  Well, that's a bit harder to track but again, the middle-of-the-road combatant gets a d8 for hit points, and they get those every level.  While the middle-of-the-road weapon is the trusty long sword, which also does d8 damage.  So, about 2 hits on average sounds right.  Well, at first level.  See, while HP increases by a d8 every level, weapon damage doesn't.  Weapons can get an extra d6 or two, from flaming or frost or shock abilities, but mostly weapons get +1 increments (from both weapon abilities and a lot of feats).  So while it may take 2 hits to kill at level 1, by level 10 it's more like 5-8 (I'm going off the top of my head, it's a pain to try to actually calculate given all the variables).  Only spells tend to do the caster's level in damage, making them much more deadly (even without the save-of-die stuff).
    So, base 50% chance to hit, with low then higher hits to kill.

    Thing is, that's not 13th Age.
    I'm not going to go into a fully detailed breakdown, I can if anybody cares and is curious but I want to keep this post kind of short.  In 13th Age our default is still the naked guy, since he is the base chance to hit that we will be modifying.  And there, the odds are a lot different.  It looks the same, naked guy has an AC of 11 (10 plus 1 for first level and no attribute modifiers).  Thing is, the generic first level monster (mook or normal) has a base/default +6 to hit.  And, 13th Age is roll equal-or-over (Pathfinder is over), which means our monster has a base 75% to hit, a bit higher than the 50% of Pathfinder.  Also, there are very few ways in increase Armor Class in 13th Age, it mostly goes up by one point each level - but so does the base monster attack bonus.  So for all levels from 1 to 10, in an on-level fight the average monster has a good chance to hit the average player.
    It gets more fun from the player's perspective.  The average 1st level monster has a base AC of 16.  Again, with no attribute modifiers, the average player gets a +1 for being first level, which means he only has a 30% chance to hit in return.  So things are in the monster's favor by default.  And again, everything goes up by 1 point per level on both sides, so this is a common ratio from level 1 to 10.
    What about hits to kill?  Well this is pretty interesting.  The 13th Age designers seemed to really want a stable system, because even though you add one die of damage per level, even though 5 different spells have 5 different damage progressions, even though there are all these numbers to confuse things - it actually boils down to all monsters and players taking about 3 to 5 hits to kill.  No matter the attack, no matter the level, no matter the circumstances - 3 to 5 hits is about how long somebody is going to be around.
    So, monsters base 75% chance to hit and players base 30% chance to hit, 3 to 5 hits to kill throughout all levels.

    Yes, 13th Age combat is a lot more deadly than Pathfinder.  My gut feeling was right.
    Now, I am not saying that one or the other is better - let me make that clear up front.  There is no "better" or "worse" to this sort of thing.  Either you like your combat deadly or you like it leisurely, it's a matter of personal taste.  But, one thing that is important and indisputable - you have to know which one your system is.  And frankly, games suck at this.  There should be a section in every GM book or chapter on the "combat assumptions" about how hard things should be to hit and how many hits to kill and what kind of fights and player behavior the game expects.  This is vitally important information for both the GM and the players to know up front, when planning characters and gear and teamwork.  And pretty much no game actually does this.  You have to play it, or get a calculator and the book, and figure it out yourself - which is pretty darn stupid when you think that the designers had to answer those same questions and could just write down what the hell they were thinking instead of making you work for it yourself.  And like I discovered, when you switch games, try something new, if its combat assumptions are very different from your experience then you're going to have a hard time playing on either side of the screen.