Weal and Woe

The recent kerfuffle over the Dungeons and Dragons OGL has me wondering whether I can turn my 2d10 conversion of D&D into its own stand-alone, non-OGL system. There's a lot I would need to do to make that work, but let's start with the advantage/disadvantage mechanic. I want to take a system where you can add d10s to 2d10 rolls, but universalize it and limit it. So to that end, let's introduce the idea of the Weal and Woe dice pools:

The Weal and Woe Pools

The universe is strangely balanced, whether by gods, some unknown purpose, or just random chance. Good luck always follows bad, and bad luck follows good. In the game, this is represented by the Weal and Woe dice pools. While dice are more tactile and intuitive to use for these pools, tokens, coins, tallies on a sheet of paper, or a tracker on a virtual table top may be used instead.

At the end of each rest, each pool starts with 5 d10s. After a player rolls 2d10, there are circumstances where he or other players may roll an additional die from the weal pool, or where the GM may roll an additional die from the woe pool. No player (including the GM) may roll more than one die from his pool for any 2d10 roll. After all dice are rolled, the players (including the GM), in the order that they rolled their dice, select one of the rolled dice (including the original 2d10 dice) and place that die in the opposite pool from the one they drew their die from. The remaining two dice are the final roll.

If any final 2d10 roll (after any Weal and Woe dice are added and the selected dice are sent to their pools) is a double, and that doubled number is greater than the amount in the Weal pool (if a player is rolling the 2d10) or the Woe pool (if the GM is rolling the 2d10), then move a die from the opposite pool to the 2d10 roller’s pool. So if there are five dice in each pool, and a player rolls two 6s, move a die from the Woe pool to the Weal pool. This has the effect of balancing the pools over time.

The circumstances where players may roll dice from the pools are the following:

1. Before the player rolls his 2d10, the GM may declare that the circumstance is either favorable or unfavorable. With a favorable circumstance, the player may choose to roll a die from the Weal pool after his roll, and select a die to discard to the Woe pool. With an unfavorable circumstance, the GM may roll a die from the Woe pool after the roll, and select a die to discard to the Weal pool. Alternatively, if it's an enemy who suffers an unfavorable condition, the player may roll from the Weal pool to cause him misfortune, and an enemy with a favorable condition gains his extra die from the Woe pool.
2. Players may select to aid another player. To do so, they must have training in the skill, or another ability relevant to what the other player is attempting. They also must forgo making an attempt themselves, and share in the consequences if the final roll is a failure. The duration over which the helper can’t make an independent attempt depends on the situation. You can help someone else make an attack by feinting, but you can’t make an attack in the same turn. You can help someone climb a wall, but you can’t make progress climbing the wall yourself at the same time. If you’re trying to help someone recall some lore, or figure out a mechanism, it’s assumed that you’ve already given it your best shot, and you can’t try again until they can, when the circumstances change—you gain access to a new tool or research materials, for example.
3. Certain ancestral, class, or other features may allow you to draw from the Weal pool either to help in your own 2d10 roll or an ally’s. On the other hand, certain monster abilities allow them to draw from the Woe pool.

It’s certainly possible for a party or the GM to burn through their pool, especially when they’re desperate. However, once one pool fills up to 10 dice, new options are on the table. At any time when the players have 10 dice in their Weal pool, or the GM has 10 dice in their Woe pool, the party (all players must agree) or GM, whichever has all the dice, can do one of the following:

• The party or the GM declares that every roll for one side in the combat has one higher degree of success, and every roll for the other side has one lower degree of success, than the dice actually show, until the beginning of the turn of the character when that is declared (I'll discuss how degrees of success work for attacks later).
• The party or the GM declares that a single roll is a double 10, no matter the circumstances of the roll.
• A party or GM can describe a lucky break, introducing a circumstance or random chance brought on by the preponderance of luck on one side. The GM may start a random encounter with a deadly foe, a player may declare the arrival of a strong ally. The circumstances of the lucky break doesn’t last beyond a single encounter.

Once the GM or party uses the dice in this way, all dice are divided equally between the two pools again immediately (after the perfect double 10 roll, but before the encounter or round plays out).

Design Goals

I like the idea of advantage and disadvantage, but I think I like it more when it's a renewable but limited mechanic. When that's the case, people are more careful about using it. If you can attack with a Weal die every turn, you're going to think twice when you start to run low, especially when there's a chance you can give the enemy all ten dice that lets him do something particularly powerful. There's an element of risk in using either Weal or Woe, especially when you're running low and there's a chance you can give the other side the last die he needs to have all ten. Even if you save the last die, he may eventually roll a double 10.

On the other hand, once you have all ten, you have a motivation to use them quickly, because otherwise the first double the other side rolls (there's a 10% chance every time someone rolls 2d10) will steal that die. Since the fewer dice in your pool you have, the more likely a double is to move a die to your pool, the system tends toward balance. (I suspect it will trend toward the Weal pool, just because the players roll more 2d10s, but that gives them a motive to spend more Weal dice too.)

I think this feels most natural when the pools contain actual d10 dice. Then you move a die from your pool, roll it, and, when it's time, put a die in the opposite pool. It's very physical, moving dice around on the table. I also like that when you help (or hinder) someone, you roll the helping/hindering die yourself, and then decide which die you remove--you don't feel shorted by someone else's poor rolls, as you're taking part in the rolling.

Finally, by letting the player and the GM decide which dice to remove, I don't feel like I need to come up with an algorithm, like I did for rolling with advantage and disadvantage with 2d10 (especially when I programmed it into Avrae). I was originally going to decide who removed the dice in which order (2d10 rolling player? GM? Other player? Should they alternate?), but I think it works best doing it in order of rolling the extra d10, but waiting until all dice have been rolled. That way if you decide you want to add a Weal die, there's always the risk that even if you roll better, the GM will take it. That will mitigate the number of dice rolled for any 2d10 check. I didn't set a hard limit on the number of dice you can roll--obviously you can't roll more than twelve, since at that point all the pools are used. But since each player is limited to 1 die, it would have to be a pretty big party to make that happen, and you'd be giving up almost all the dice to the GM (or all of them, if he didn't roll one).

One thing to note is that, as dice move from one pool to another, people's personal dice can go into a pool. People should probably have different colored dice if they want to make sure they get their dice back. I'd also allow them to trade a d10 for their personal die in one of the pools.

Example

There are two dice in the Weal pool, and eight in the Woe pool. The rogue is planning to climb a wall, but it's dark, and as a human, he can't see in the dark. The GM declares that he has an unfavorable circumstance. The fighter and the ranger are both skilled climbers, and importantly, can see in the dark, so they declare that they will help the rogue up the wall. The GM rules that they can, but they can't climb the wall themselves until the rogue's climbing is resolved, and if he falls, he'll land on them and they'll take damage as well. The players agree, and the rogue starts climbing.

The rogue rolls 2d10, and gets two 6s. A high double! The GM decides to spend a die from Woe, and rolls a 2. Seeing this, the fighter rolls a die from Weal, and also gets a 2. The ranger notes that their Weal dice pool is running dangerously low, and opts not to roll, hoping that it'll be good enough.

The GM removes a die, taking one of the 6s and putting it in the Weal pool. Then the fighter removes a die, and places one of the 2s in the Woe pool. The rogue is left with a 2 and a 6, or 8 plus his modifier. If that's not enough and he falls, the ranger may regret his choice when the rogue falls on him and the fighter!

Later, when the ranger decides to stealth ahead, he rolls 2d10 and gets two threes. A low double and one degree of failure, but since the doubled number is higher than the two dice in the Weal pool, one die is transferred from the Woe pool to the Weal pool. Now it's three dice in the Weal pool and seven dice in the Woe pool.