Beoric
8, 8, I forget what is for
The table is more art that science, largely because 1e's progressions are more art than science. It is way easier to convert from 3e or 5e.Hmmm I like this, and the numbers make sense to me.
Just wondering. Ogres individually have 4+1 HD in 1st. So 10 ogres would be about 40 HD. You have 18 here. If we account for their damage resistance, that's an 'effective hit dice' of 36 vs. individuals, certainly close enough for me. Do you think it would be different if we skipped that special ability and just gave the squad 36-40 straight up HD? I suppose this must be balanced against the damage each unit deals against other units as well as against individual PCs.
How does this conversion table of yours work that you mentioned above? I have never played 4th but perhaps it might be useful to those of us who like juggling things around between various editions.
You can't assume it will work to just add hit dice because HD aren't just a measure of hit points, they are also a measure of accuracy, and they have an impact on XP calculation. Your other measure is XP, but XP increases geometrically (more or less), while monster power does not increase geometrically. So there is no baked in way to figure out how much tougher a single creature is than 100 creatures working together. And there is also no baked in way to relate the increase in power caused by a larger number of low level creatures to the increase in power caused by a PC gaining levels. I tried relating the two using the Appendix C numbers for how many creatures of a given "monster level" you use on lower levels of a dungeon, and it just doesn't work. You may encounter twice as many orcs on level 2, but a level 2 party is not twice as tough as a level 1 party.
In 4e it is different. With 4e mechanics it is possible to say, for example, that 64 level 2 orcs are exactly 64 times tougher than one level 2 orc. There is also a known relationship that both monster power and PC power doubles every four levels. So I can estimate with a fair level of confidence that 2 orc raiders (a level 3 standard monster) are about the match of one level 3 fighter, 4 orc raiders (possibly rebuilt as level 11 "minions") are a match for a level 7 fighter, and 8 orc raider "minions" are a match for a level 11 fighter. I can also take 16 orc raider minions and make them into two fifteenth level swarms that would together be a match for a 15th level fighter.
Because 4e power levels are easy to manipulate, and I have a reasonable amount of confidence in my conversion chart, it was easier to convert a single creature to 4e, figure out the power level of a swarm of the appropriate number of creatures, and convert it back.
So, about my conversion chart. The first thing you have to know is that "low level" in 4e covers about twice as many levels as it does in 1e. The big limiting factor is access to utility spells, because that determines the sort of adventure you can go on. For instance, levitate, water breathing and fly change the game. Most level 1 utility spells, which are available at 1st level in 1e, are not available until 2nd level in 4e. Likewise, 2nd level utility spells, which are available at 3rd level in 1e, are not available until 6th level in 4e. And 3rd level utility spells, which are available at 5th level in 1e, are not available until 10th level in 4e. After that they tend to progress at roughly the same rate (until you get to 9th level spells where it all breaks down).
The point being that a level 1 PC in 1e is the equivalent of a level 2 PC in 4e. That was a fixed point for me. A level 3 PC in 1e should be roughly equivalent to a level 6 PC in 4e, and a level 5 PC in 1e should be roughly equivalent to a level 10 PC in 4e, but the relationship is more shaking because 1e classes rise at different rates from each other, and power level varies wildly in 1e depending on what magic items you have.
Figuring out power level is even worse with monsters, because a monster with n HD and no special abilities is considerably weaker than a monster with n HD and a ton of special and extraordinary abilities. The only number that seemed to rise consistently with power level is monster XP value. So I decided to relate 4e monster level to 1e XP value.
I figured that in 1e a hobgoblin is about a match for a first level fighter. They have about the same AC, do about the same damage, and have about the same chance to hit and the same number of hit points (well, before Unearthed Arcana, anyway). So I decided that a 1e monster with 31 HP was the equivalent of a 4e PC of level 2, or a 4e elite monster of level 2. I then searched around for other touchstones so I could start building a progression, and did module conversions with the numbers to see if the resulting calculations matched my expectations.
What surprised me was that, using the progression, a number of 1e monsters ended up having exactly the same power level as their 4e equivalents. The best example of this was Demogorgon. The "on the prime material plane" XP value for Demogorgon ended up equating to the 4e "Aspect of Demogorgon" with the exact same power level.
Other 4e creatures ended up being exactly half as powerful as their 1e counterparts, likely because 4e preferred battles with more opponents - so you would encounter them at the same relative level, but there would be twice as many of them. The ogre is a good example of this.
I ended up having to use a different progression for monsters of 1 HD or less; it turns out that a 1e orc, which is worth half as many XP as a hobgoblin, is also half as powerful. This probably resulted because fighters over 1st level get multiple attacks against groups of monsters with less than 1 HD.
Anyway, with the ogres, I established that a 1e ogre is equivalent to a 4e level 6 elite monster worth 500 XP. 1 ogres therefore form a swarm with 5000 XP, which would be a level 23 standard monster. A 4e level 23 standard monster is roughly equivalent to a 1e monster with 10,000 XP. I then tinkered with the number of HD, taking into account the value of the special abilities the unit had, until I ended up with an XP value as close as I could get to 10,000.
To figure out values for attacks on heroes and other monsters, I made a guess at how many ogres could attack an adjacent medium creature without breaking formation (1 or 2, so 1.5), and how many could attack an adjacent creature of the same size (3), and went through the same procedure to figure out their equivalent hit dice for the chances to hit smaller targets. Because if a hero attacks the ogre unit, he isn't attacking the whole unit at once, and not every ogre in the unit can attack him without breaking formation.
Now, the ogre unit has less hit points than the sum of the hit points of 10 ogres, but (a) hit points are an abstraction; (b) they take half damage from melee attacks from the PCs; and (c) the hit points are not the total required to slaughter every ogre, but the total required to break up the unit and have the survivors flee, retreat or surrender.
The one thing I couldn't do was determine damage from unit-on-unit attacks, because I haven't played 1e since the 90s and don't know it intuitively. I could look at examples and try to figure out what damage I expect a 18 HD monster to do, but I figure the people who might actually can probably figure out that number easier than I can.