I've recently started playing Amazing Tales with my children. As a summary of basically all the mechanics of the game (it's pretty simple since it's targeting children), each character has four skills, each of which is assigned one die from the four available (d6, d8, d10, d12). When the GM wants to call for a skill check, he determines the appropriate skill, and the player rolls that die. A 3 or greater indicates success, and a 1 or 2 indicates failure. The GM then continues narrating, trying to keep the story interesting based on what happened.
The challenge I'm running into is that my children often want to play opposing sides. (That is, one will be the "good guy" and another will be the "bad guy" of whichever fictional universe they want to play in that day.) The rules as written pretty much assume that the entire party is on the same side, and doesn't have any sort of player-vs-player mechanic. But the stories we're coming up with are fun for the group, so I think that PvP is working for us. I think it'd help me with some of the narration, though, if we had some sort of "opposed roll" mechanic for when two players are trying to do something directly in opposition to each other.
My first instinct is to just pick an appropriate skill for each character, have the player roll the die for it, and the highest die wins. While that certainly accomplishes my objective, I'm a bit worried about it being too "swingy" if the dice are significantly different. That is, if the d6 skill of one player goes against the d12 skill of another player, then (if I did my math right) the d6 player would win ~21% of the time, and the d12 player ~71% of the time (with a tie the remaining ~8%).
I'm looking for something with a bit more "bounded accuracy" (if that's the right term), where having a better skill gives some advantage, but not a really big advantage. Maybe something where the favored player is likely to win more like 60% of the time, though I haven't really thought through what the ideal number would be.
My next thought is something like "1d20 + the skill die", where the d20 adds a lot of "randomness". But I'm not sure how close this meets my needs, and I know that adding more dice generally ends up ironically reducing the "randomness" by lowering the standard deviation, and I'm not sure how to fully evaluate how adding more dice to rolls helps with the overall probabilities. I will probably playtest this at our next session unless I get a better idea, though.
So I'm looking for an answer of what mechanics I can use to do a PvP opposed roll, with different skill levels of the players, within the simplified skill-checking system that Amazing Tales has.
- Using a better skill should give some level of advantage, but not a big advantage. The odds should be 50%/50% if they're using the same skill, and somewhere near 60%/40% (though this is negotiable) if they've got the biggest gap in skill (d6 vs. d12).
- Really simple and quick to calculate, since this is being used by children without much patience. Rolling two or three dice and adding them, or taking the highest, or something like that is about the most complex I want to get. If there's a lot of cases and rerolls of numbers or whatnot it gets tough to explain and would take us too much time during an exciting action scene.
- I expect it should use the skill die itself in some way, just because that's the core of the system and it can be helpful to put the physical die on top of the skill on the character sheet. (That is, rolling some other die and just adding the skill die size seems like it's not in the spirit of the system, though perhaps something like it may work too.)