MSFD Derived attribute calculations
(Thanks to DinkumThinkum for this info.)
The following is based on how they're calculated for player characters; checking in the Construction Set, NPC derived attributes appear to use basically the same system (if auto-calculate is enabled).
Maximum Fatigue: equals the total of current Strength, current Endurance, current Willpower, and current Agility.
Maximum Magicka: current Intelligence times the character's magicka multiplier (varies with race and birthsign).
For NPCs, the multiplier apparently is fixed at two (default value of fNPCbaseMagickaMult: see Game Settings); race doesn't seem to affect it.
NOTE: this is based on the Maximum Magicka shown in the editor. Racial abilities that fortify Maximum Magicka are listed in the 'spells' section of the NPC's properties page, so that may be figured into the maximum value used during game play; haven't tested this.
Maximum Encumbrance: five times the character's current Strength.
Maximum Health (player): When you create your character, their starting maximum Health (at first level) is one half the total of their Strength and Endurance.
After that, each time your character goes up a level their maximum Health is increased by 10% of their Endurance (value set by fLevelUpHealthEndMult, see Game Settings).
This is based on the character's base natural Endurance; magical modifications to Endurance are ignored.
Strength is only used to calculate the player character's starting value for maximum Health; it has no further affect on Health once the character has been created.
Also, Endurance affects the amount added to the character's maximum Health each level; there's no recalculation of the amount added in previous levels.
Maximum Health (NPCs): A number of formulas for NPC health have been proposed, but I (melian) have yet to find one that works for more than one NPC.
At base level, NPC Health appears to be auto-calculated in the same way as the player's: (STR + END)/2.
After that it gets tricky, and most formulas fail quite dramatically at higher levels.
For some NPCs: The calculation is based on the character's Strength and Endurance, and Health increase factor per level is constant within three brackets: before STR has maxed (largest increase), after STR but before END has maxed (smaller increase), and after both have maxed (constant smaller increase from then on). It's usually easy enough to calculate a single NPC's Health at any given level by noting Health, Strength and Endurance at various levels and working out the increase factor per level in each of the three brackets (remembering that values are really floats: averaging a larger value will get a more accurate increase factor). This has worked for most NPCs I've used it on, whose Strength maxed well before Endurance did. I'm not sure of the progression for NPCs whose Endurance maxes first, and race may have something to do with it as well.
