House Rules: Optional Random Spell Duration System

by Doug Rosengard

Date: Mon, 9 Dec 1996 19:58:50 -0500 From: Doug Rosengard To: Multiple recipients of list Subject: Optional Random Spell Duration System

I was thinking about spells and charged items the other day and it occured to me that it might be fun to implement a magic system that keeps spell casters on their toes by making spells last for more unpredictable durations. After all, magic is chaotic and barely managable at best, so why should spell casters know precisely how long a spell is going to go on?

I remember seeing an optional rule somewhere that suggested this idea, perhaps by varying spell durations by up to plus or minus 10%. I'm considering something different, however, and I'm curious to see what other player's reactions are.

I'll start with charged items (ie wands, staves and rods). I already use an optional rule for these items that works as follows. Rather than have a specific number of charges, a charged item is either "charged" or "not charged". Each use of the item has a chance of burning out the remaining power, making it the last use until the item can be recharged. The burnout chance is equal to 1/[number of charges in a fully charged item]. So, for instance, a wand, which normally has 10 charges, would have a 1/10 chance of burning out after each use. Burnout rolls are made secretly by the GM, since players would only be aware of a burnout either through spell use or trying to use the item again.

Any spell that would normally tell a character how many charges an item has now tells them what the burnout chance is if the item is "charged up", or will tell them that the item is not currently charged-up. The only way to really know for certain how many successful uses an item will deliver is through a precognitive spell of some sort.

This system has a couple of effects on item use. First, characters are more cautious when using magic items since they can never know if the next use will be the last. Second, you never have to worry about keeping track of charges, cutting down on bookeeping. ("Did the staff have 23 or 24 charges left last month?") Lastly, it's fun to have players holding their breath every time an item is used, hoping it will still work. Never will a player have a wand recharged and know he has even 9 or 10 charges. Maybe the wand will work 10 times, maybe it will work 20 times, or maybe it will only work once! What fun. :)

As I've said, the above rules for charged items are already in use, and work well. The idea I'm considering currently is a similar one for spells.

This optional system only effects spells that have a duration other than "C" and Permanent spells.

Spells that last exactly one round are unaffected; they still last exactly one round.

For spells that have a duration of "n rounds" for some number n, this system assumes the spell works like a charged item. Either it's working, or it's completed. The exact duration of the spell is unknown - all that is known is the expected average duration of the spell. At the beginning of each round a spell of duration 'n' rounds is working, the spell has a 1/n chance of burning out at the end of the current round. So, at the start of the round, the GM makes a burnout roll with a 1/n chance of burnout. A burnout result means the spell ends at the end of the round.

For example, take a spell that normally lasts 5 rounds. It is guaranteed to work one round, and has an 80% chance of working at least two rounds. It has a 51% chance of lasting at least 4 rounds, 41% of at least 5 rounds, 33% chance of at least 6 rounds and so on. The spell has a 13% chance of lasting ten rounds or more, and a little over a 1% chance of lasting 20 rounds. Whereas a little over half the time the spell doesn't last as long as 5 rounds, there is a small but reasonable chance for the spell to last much longer than five rounds.

For spells whose duration is listed in minutes, hours or days instead of rounds, simply use the above system substituting the appropriate time unit for "rounds" above. Thus a spell which lasts 10 days has a 1/10 chance of burning out each day. The exact burnout time (eg what time of day the spell dies out) is determined randomly.

I think this would have an exciting effect on spell use overall. Spell casters would be like professional gamblers, playing the odds that their spells will last at least a certain duration. Also, they can in times of need cast a spell hoping it will last a little (or a lot) longer than normal. They will never be able to cast a spell then set their sun-dials by it.

The GM should make burnout rolls at the start of the round to see if it is the last round of the spell. The character who cast the spell could make a Routine spell casting static maneuver roll to tell if the spell is ending on a given round (ie he senses the spell is sputtering out). One further possibility is to allow a character with Time Sense and Spell Mastery to make medium maneuver rolls in each to force a spell to last its "normal" duration. Thus a character with both skills could cast very precisely timed spells that last exactly as long as they are supposed to.

That's about it. I unfortunately will not be in a position to try random spell durations for a little while, but if anyone else thinks it sounds interesting, and gives it a shot I'd be interested in how it turned out. My guess is that it would add some real spice to otherwise mundane spells. ("What do you mean the Fly spell is burning out?! ")

-dug@lugaru.com


Back to the House of Rules.