Custom Roll Alias

[Immanius]

I'd like to request a dice alias for the 1997 release of Alternity.

Alternity uses difficulty degrees to determine what the needed dice roll is. The skill check is made up of a Control Die (1d20) and a Situation die (variable based on difficulty) that result is then compared to the characters skill to determine the degree of success

Difficulty | Roll
  -5 Steps | 1d20-1d20
  -4 Steps | 1d20-1d12
  -3 Steps | 1d20-1d8
  -2 Steps | 1d20-1d6
  -1 Steps | 1d20-1d4
   0 Steps | 1d20
  +1 Steps | 1d20+1d4
  +2 Steps | 1d20+1d6
  +3 Steps | 1d20+1d8
  +4 Steps | 1d20+1d12
  +5 Steps | 1d20+1d20
  +6 Steps | 1d20+2d20
  +7 Steps | 1d20+3d20
+N>4 Steps | 1d20+(N-4)d20

Degree of success is determined based on the characters skill in the following manner
There are two "types" of checks generally referred to as MOGA and FOGA
MOGA = Marginal, Ordinary, Good, Amazing
FOGA = Failure, Ordinary, Good, Amazing

the system is roll low

Critical Failure = if the first 1d20 (control die) is a natural 20, seeing the control and situation die result can be very helpful for house rules and odd ball situations
Marginal Success / Failure = any result over the skill check
Ordinary Success= any result equal to or less than the skill check
Good Success= any result equal to or less than on half the skill check (rounded down)
Amazing Success= Any result equal to or less than one quarter the skill check (rounded down)
Critical Success= any degree of success with a natural 1 on the control die, seeing the control and situation die result can be very helpful for house rules and odd ball situations

Ideally, the syntax would be something similar to:
!roll Alt type (step) (skill name) (rank)

and the result would be displayed similar to:
[roll requester] [skill name] [control die] [situation die] [Die math] vs [skill rank] = [result category]
IE:
Senario punching a punching bag
!roll alt m -2 Brawl 17
Immanius: Brawl 13 -3 = (10 vs 17) Ordinary Success

Coding an esoteric die mechanic
!roll alt f +6 Programming 26
Humblemonk: programming: 1 +22 = (23 vs 26) Critical Success (if it were combat, I'd rule this as a good success due to the rules surrounding amazing successes and combat)

Watching Sesame Street in a foreign language
!roll alt m +2 german 17
DavidHasslehoff: German: 14 +6 = (20 vs 17) Marginal Success

Trying to shoot The Flash
!roll alt f +7 firearms 12
Everyman: Firearms: 19 +11+18+19 = (67 vs 12) Failure (Personally I'd house rule this as a critical failure, but RAW it's just a regular failure)

jogging down the street
!roll alt m -4 race 21
ScottSummers: Race: 20 -12 = (8 vs 21) Critical Failure

Please feel free to contact me if more information/clarification is needed.