The Aurora RPG Engine – Part 13

Postscript 4 – MoS Counting

It’s somewhat thorny to get an idea of an average numerical value for MoS that includes the possibility of failure, since both failure and an MoS of 0 calculate as zero.  However, if we look at mechanics for using MoS either in cumulative or extended tasks, or when it is used to determine damage or an outcome against an opponent, we can calculate some useful guidelines (and get a window on how to use those values in our game).

There are two prime methods to use MoS in this way.  The first is to have a success (MoS of 0) count as 1, plus 1 additional per point of MoS.  So a success with an MoS of 2 would result in a value of 3, whether that be 3 points of damage/effect, or 3 points added to the cumulative pool towards completing a task or achieving an aim.

Using this, we can determine the average MoS expected for a particular dice pool that includes failure:

An alternate way is to re-work the success ladder presented earlier to make an MoS of 0 a little more precarious by making it a Minimal success:

MoS Quality of Result
0 Minimal Success
1 Solid Success
2 Notable Success
3 Brilliant Success
4 Stunning Success
5 Sublime Success
6 Legendary Success

Thus a Minimal success is a case where the character has just, barely, succeeded at the task.  For example:

  • If a character is leaping between buildings, their foot lands right on the edge of the parapet. They made it, but their heart is certainly beating hard now!
  • If this leap was part of a chase, it may cause them to stumble a bit, which, depending on how their quarry rolls, might make them lose a bit of ground.
  • If the character was attempting to haggle for an item, they only manage to get a minor discount.
  • If the character was researching something, they confirm its existence and the overall, general information about the thing, but nothing very detailed.
  • If the character was fixing an engine, they get it running in the nick of time, but it was looking dodgy right up until the last moment!

This is opposed to the next rung up the ladder, where a Solid success is an unambiguous one:  a character lands firmly on the roof beyond the parapet; they achieve a worthy discount; they gain a new piece knowledge that will aid them going forward, or they get things running and are sure that things won’t break again.

The value of making a distinction between Minimal and Solid success is mostly one of RP – it’s to narrate a bare success.  It also helps to make each of the levels above a Solid success more distinct and thus easier for the GM to craft mechanical and narratively appropriate outcomes (and thus also more RP-rich).

Minimal success can also be used to tweak the cumulative/damage mechanics by having the value be equal to the MoS, with the special case that an MoS of 0 counts as a value of ½.  This makes things more elegant and straightforward* to calculate as there’s a more direct line between the MoS and the value (when compared to calculating it as the 1 + MoS method above).

Using this Minimal success method, here is the matrix to determine the average MoS expected for a particular dice pool:

*While keeping track of ½ points of success might seem to add back some inelegance, but as the system is already tracking ½ values for the dice pool the context for ½ points already exists.  Much like modifiers described above, it could be recorded using boxes, where a ½ result is marked by placing a single slash in the box and a full point is marked either with an X in the box or by completely filling in the box.

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