Roll a bunch of D6s.
LENGTH: The value of the highest D6; if you get multiple 6s, each one counts as +1
HEIGHT: Select any die showing in your pool. This is the height of your pool.
WIDTH: Count the number of dice showing the number you selected for the height. The number of dice is the width of your pool.
For example, say I roll 6 dice and get:
2, 3, 3, 1, 1, 6
The length of the pool is 6. The height can be 1, 2, 3, or 6. The player decides to make the pool height 3. The width is thus 2, because there are two dice with "3" showing.
With this system, length will tend towards 6 (especially once 3+ dice are rolled). Height will be highly variable depending on the player's desired effect. Width will tend to be a smaller number (2-3 with dice pools of <5).>
Note: This is similar to the Godlike system, apparently:
And here's some odds:
Let's say you want to cast a summoning spell. The relevant factors are:
1) How powerful is the critter that shows up? The critter will have HD equal to the caster's level + X - 3.
2) How friendly is the critter that shows up? Make a reaction roll immediately upon completing the spell, with X as a bonus to the roll.
3) How long does it stick around/how hard is it to dispel (Potency)? The potency of the spell equals X. Every round on your initiative roll 1d6. If its less than the potency, the spell continues. If you roll equals or exceeds the potency, the spell ends.
In all cases, X = height, width, or length.
The player decides that he wants to be able to control how powerful the monster is, so he assigns that factor to Height. He also wants to be able to maximize its Potency, so he assigns that as Length. That leaves the friendliness of the monster to be governed by Width.
The mage rolls five dice and gets 1,2,1,5,5 (I actually rolled that pool).
POTENCY: The potency of the spell is easy to determine -- that's 5. Every round the magic user rolls 1d6. The spell will stick around until the magic user rolls a 5 -- so it will stick around for around 3 rounds.
POWER: The player can then choose 1, 2, or 5 for the power of the monster. The player wants a strong critter, so he selects 5. The critter has 2 more HD than the mage.
REACTION ROLL: There are two 5s, so that means the friendliness is 2. The mage immediately makes a reaction roll at +2. We'll see if the his scary monster is willing to help, or if it will turn on him...
I like this system for magic because it makes spells more mysterious. The odds are harder to predict before rolling and spell results might be unpredictable (although not so much that the game designer can't predict most likely outcomes). Yet, its easy to tabulate the results and apply them.
You could run this, action wise, in a few ways:
- ROUND 1: Declare parameters of spell
- ROUND 2: Roll dice pool, determine results
- ROUND 0: Parameters of spell are pre-determined
- ROUND 1: Roll dice pool, determine results
- ROUND 1: Roll dice pool
- ROUND 2: Roll more dice, add to pool
- ROUND 3: Roll more dice, add to pool, etc...
This method is cool because the caster could keep going if they don't have the desired results yet, but they don't necessarily feel like they are wasting their round (i.e., they get to roll dice and make a decision). It makes that priest in the back row who is chanting pretty threatening, because every round his odds of kicking off a bad-ass 6/6/6 spell go up.
ADDENDUM: This is now known as the "Spell Matrix." Labels added to posts as appropriate.