In my opinion, AttackMulSet is best used for a global Damage Dampening feature in MUGEN.
Seravy has made a nice global Damage Dampening topic at Elecbyte wiki here: http://elecbyte.com/wiki/index.php/Damage_Dampening
If only some sword attack states' damages depend on distance between P1 and P2, then I think you might consider working on the Damage = value,value in your sword attack states' HitDef(s), some example like this:
[State 210, Medium Sword Normal Attack]
type = HitDef
trigger1 = AnimElem = 3
attr = S, NA
animtype = Mediumdamage = IfElse(Ceil(P2Dist X) >= 150, 50, Abs(-150+Ceil(P2Dist X)-50))
guardflag = MA
pausetime = 12,12
sparkno = 1
sparkxy = -10,-70
hitsound = s5,3
guardsound = 6,0
ground.type = High
ground.slidetime = 12
ground.hittime = 16
ground.velocity = -5.5
air.velocity = -2.5,-4
Assume the longest distance the sword of this Medium Sword Normal Attack can reach P2 is about 150.
The "damage = IfElse(Ceil(P2Dist X) >= 150, 50, Abs(-150+Ceil(P2Dist X)-50))" line
of MUGEN code
read like this:
- "if the Medium Sword Normal Attack is barely reaching P2 at the distance of 150 then its base-damage value is 50. When it is getting closer to P2 then the damage increases based on the P2Dist X Trigger. The Abs Trigger is important because it can prevent from healing P2.
So, the values "150" and "50" are the ones you are changing for your case.
Sorry my math is bad and this is what I can come up with...........
Perhaps someone better can provide a more improved version to you..........