Tuesday, January 3, 2012

MUTANTOR! Mutant Dice

I'm starting work on MUTANTOR! and one of the things I want to nail is a dice engine mechanic that reflects the setting. So yeah— MUTANTOR! is obviously gonna be crawling with mutant freaks, and the game mechanic should be something like that too.

I'm torn here; there's a strong temptation to make MUTANTOR! another OSR permutation, and stick with the d20 for combat and skill resolution. But if I go my own way here's what I'm thinking of doing.

The MUTANTOR! mechanic would look something like this:

Roll three d6 dice, scratch the highest and lowest roll take the middle dice as your result.  Equal or beat the difficulty to succeed.

If you roll Doubles (two dice have the same face), add 1 to that face, that's your result.

If you roll Triples (all dice have the same face) add 2 to that face, that's your result. Plus the dice MUTATE!

For the player that rolled the triple, from now on their dice rolls have MUTATED: anytime that face turns up in following dice rolls it gets treated like a wild die or joker and the player gets to choose what that die should be.

Any mutant dice roll can mutate into a MUTANT Double. 

If you roll a natural MUTANT Double it can mutate into MUTANT Triple.

If you roll a natural MUTANT Triple... a MEGA MUTATION or something big and cool and I don't know what yet*.

The MUTANT dice effect lasts until the player uses the dice to form a MUTANT Triple, or they roll a natural MUTANT Triple, or the game session ends.

From what I can tell about the probabilities, it all looks something like this:

chance to roll any particular combination : 1/216 (0.46%)
chance to roll a Double : 90/216 (41.67%)
chance to roll a Triple : 1/36 (2.78%)

once mutated:

chance to roll and mutate into a MUTANT Double : 75/216 (34.72%)
chance to roll and mutate into a MUTANT Triple : 30/216 (13.89%)
chance to roll and mutate into a MEGA MUTATION : 1/216 (0.46%)

*MEGA MUTATION... I'm thinking that the player's dice pool permanently mutates; something like one of their three d6's evolves into a d8. next megamutation the another mutates into a d8 again, til they're rolling three d8s... and then d10s, then d12s, and so on.

So yeah. there you have a it, a straight forwardish dice mechanic that reflects the nature of the game.

I'd really like your thoughts on it, whether it works or has loopholes or can be over exploited or whatever. Cause once the system is locked in then I can get cracking on the rest of MUTANTOR!

Some samples of dice rolls:

Normal rolls: drop the highest and lowest
146 = 4
456 = 5

Doubles: take the double face and add 1
225 = 2+1 = 3
323 = 3+1 = 4    
616 = 6+1 = 7

333 = 3+1+1 = 5 AND the dice mutate, with any roll of 3 becoming a Mutant roll

Normal Mutant (where for example 3 is the Mutant)
125 = 2 (no mutations)

Mutant Doubles (3 still the Mutant)
315 = double 5 = 5+1 = 6

Mutant Triples (3 again)
344 = triple 4 = 4+1+1 = 6, and the mutant dice effect ends.
336 = triple 6 = 6+1+1 = 8, and the mutant dice effect ends.

MEGAMUTANT (3 is still the Mutant)
333 = wacky mega effect, and the mutant dice effect ends.


  1. -I think the math should be rejiggered so a double is a +2 and a triple is a +3, just so its easier to remember

    -AS savage worlds players know, its easier to roll doubles on smaller dice, so if you are using d6s and d8s etc. you might want to purposefully use this fact to yr advantage

    -since the mutant effect ends when the session ends, and everyone is paying attention to their die rolls all the time, I think it would be nice if the rest of the game were consciously designed around using the session as a unit of play. if you are making people think about the dice that much (its almost as dice-conscious as craps) then i think the idea of unstable mutation and short-term story ideas built around said mutations should be made into a strength rather than a novelty. like maybe each mutant die represents an actual mutant body part or whatever that explains the success of the mutated roll and is there either temporarily or forever.

  2. Interesting...

    But I am a little confused. I'll re-read it and I am sure that I will get it clearer, but one thing that immediately sticks out to me is that rolling:

    3, 4, 5 = 12

    while rolling:

    2, 2, 3 = 7 + 1 = 8

    And yet there is meant to be something "special" about that second roll?

    If it is just the building to mutate up a dice set, then I guess that is O.K, but it seems that the +1 or +2 bonus won't be that helpful in half of the rolls with doubles or triples. They'd still get beaten by a standard "three different numbers" roll.

    Perhaps that is O.K; but perhaps you need to up the number bonus to doubles and triples: perhaps 3 and 6? (Or half whatever dice you are rolling, and Full score of the dice you are rolling?)

    I'll also have to go off and roll some real dice, and experiment. See what comes out.

  3. yep. drop the highest and lowest and take the middle.

    126 = 2
    514 = 4
    316 = 3

  4. in an hour I'll add a bunch of examples that I should have included for each type of roll.

  5. Ah, of course. Must have missed that bit. Well, that makes it a bit better. Makes rolling something with two 1s in it not QUITE so sucky....

    Yeah. That makes more sense, and is better. Sorry I missed it. But the examples do make it more clear.

  6. I'm new to this blog, but you had me at the MUTANTOR graphic.

    I dunno what it is, but I certainly want it!

  7. Seems pretty cool. I like Zak's suggestion. What if double 6s cause positive mutation and double 1s cause a negative mutation or atrophy? Very excited to see where this goes.

  8. Seems complex. How about the same 3d mechanic, but the dice mutate into non-d6's over time? For the most mutation, anytime you roll max on a die, in the future it bumps up a die type, roll min, it bumps down. For slightly less mutation you could go with doubles/triples or whatnot but it might be nice to reserve that for a crit mechanic. And you get to use all your dice!