Bag o' Nifties: Tricks for GMs

Fun with Target Numbers - Tricks and Gimmicks for Target Number

by Dan Bayn
Mar 05,2003

Fun with Target Numbers - Tricks & Gimmicks for Target Number Systems

The Problem

The vast majority of RPGs use target numbers in one form or another. Percentile systems usually have you roll under them. Stat + Skill systems either have you roll under or add a die roll on top to beat a GM-determined target number. Dice pool systems often do double duty, applying a target number to each die, and then requiring a certain number of successful rolls. If you have to roll over or under something, you're probably using a target number system. (I'll be assuming a roll-under system in the rest of the article.)

These kinds of mechanics have the potential to run quite fast, since humans can recognize greater-than and less-than relationships almost instantaneously. The problem, as with most things RPG, is that play can get slowed down by math, particularly by situational modifiers. Math, in general, is not my friend, and I've devoted a ponderous number of hours to engineering its obsolescence. The gimmicks below are a sampling of the fruits of those labors; tips and tricks for manipulating target number systems without resorting to tedious calculation.

The Solution: Target Number Gimmicks

I visited this territory briefly in my column on the Double Check, a meta-system for dangerous & unpredictable magic. It uses a pair of actions for spellcasting: a Power Check and a Control Check. Spells fail, work, or spiral out of control based on which checks succeed. However, the philosophy behind that mechanic can be applied to a host of other situations...

Multiple Actions - Have players roll for their first action normally. If it fails, all their other actions fail as well. (This is why it can be smart to try the most important action first, even if it doesn't have the highest target number.) If it succeeds, they can go ahead and roll for their next action, but its target number cannot be higher than whatever they rolled for the first action. For example, if the first roll comes up a 4, and their target number for the second action would normally be 6, it's now reduced to 4. Any further actions work the same way, resulting in a continuously shrinking chance of success, without looking up a single modifier or doing a bit of math.

Counter-Attacks - A little twist on that gimmick can give you a quick-n-easy way to do block-grab combo moves and Jedi-style lightsaber ripostes. If an attacker fails their attack roll, and the defender succeeds in their defense roll (should they get one), the defender can immediately roll again by using their defense result as the new target number. If the second roll succeeds, it counts as a successful hit against the attacker. (No counter-defense is allowed.) This means that more skilled attackers will get bitch slapped less often, because they leave themselves open (fail attack rolls) less often.

Inverted Stats/Skills - Sometimes, a character's best assets can work against them. Take a big, brutish bruiser trying to blend into a crowd of vegetarian protesters, for example. Force the bruiser's player to roll against whatever stat or skill governs their incredible size and strength. If they fail the check, they can successfully blend in. If they succeed in the check, they stick out like a sore thumb. My favorite way to use this gimmick is for lunatic spellcasters: I give them an Insanity stat that they use to cast spells, but force them to make inverted rolls to control their paranoid thoughts, make rational decisions, and interact with sane people. Mwahahaha!!!

Persistent Successes - You can also use the result of one character's action as the target number for another character's subsequent actions. This is most useful for things like arm locks, choke holds, and other kinds of restraints. The better the attacker's success, the harder it should be for their opponent to break free. Either write down the attacker's successful roll result or keep their die on the table. Any time the victim tries to do something that would be hindered by the restraint, they have to roll below their own target number and above their attacker's roll.

Helping Hands - A similar trick can be applied to characters who want to help each other on a single task, like a pilot trying to talk someone through landing a plane. The pilot makes their roll first. If it succeeds, the non-pilot can roll against either their own (unskilled) target number or the pilot's roll. This gives them better odds than if they were on their own, but not as good as if they actually knew what they were doing, and all without a single act of accursed addition or subtraction!

Bonus/Penalty Dice - Another simple way to replace mathematical modifiers is with a re-roll mechanic. It's very grainy, but it gets the job done. If things are lining up in a character's favor let them roll 1-3 extra dice and keep the best result. If things aren't going so well, force them to roll 1-3 extra dice and take the worst result. This benefits characters with moderate target numbers the most; weak characters will feel the most pain from a single Penalty die, while powerful characters won't even flinch at two. Personally, I think that is as it should be.

If your target number system requires you to add a pool of dice together, you can take Over the Edge's more subtle approach. Bonus dice are added to the pool and players get to drop the lowest result before adding the dice together. Penalty dice work the same way, except that players have to drop their highest die before adding things up. In this version, each die confers a much smaller (dis)advantage.

A Note on Jedi Fu

As alluded to above, the counter-attack gimmick was designed for Jedi-style lightsaber ripostes. I playtested it extensively in the course of writing my Nameless RPG Guide to Star Wars (as Directed by John Woo & the Wachowski Brothers). It's a brief re-invention of the Star Wars universe in the style of Hong Kong action movies. Nameless uses a deck of cards, instead of dice, so you can leave the first draw on the table while you make your second draw, which means you have to do even less thinking and remembering! Woo hoo!

Next Time: Quick-N-Easy LARP Combat!

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