Hail Mary Mechanic

Adventurers love a tight spot and sometimes need to pull out all the stops. Call it a Hail Mary or a do-or-die effort. Conan at the end of "Red Nails," Indiana Jones being chased by a rolling boulder, Hoops McCain replacing the halyard in "One Crazy Summer." I've played around with such a mechanic in Chimera, but working on a super-secret S&W project,[1] I offer this:

The Clutch Situation
When a character has to dig deep, here's what he can do:

Pick any die (d4, d6, d8, whatever) and roll it. If the result is less than the character's level, the action succeeds; otherwise the action fails. The action could be anything that the PC wants to do: a skill roll, find secret doors roll, surprise attempt, attack roll, reaction roll, saving throw--anything.

Regardless of success or failure, once a player declares a Clutch Situation, the die used is "locked." This means two things: (1) that die cannot be modified--every time that die is rolled (for whatever reason), the result is face value, and (2) that die cannot be used for another Clutch Situation.

The only way to "unlock" the die is to roll the character's level or higher next time the die is used. Once the die is unlocked, modifiers apply again and the die is used normally. But--important point--the PC could have multiple locked dice if he declared more than one Clutch Situation. This seems to be a throttle on abuse by players trying to game the system.

Here's the trick: the optimal die to use is the smallest die whose highest result is equal to or greater than the character's level. So while a high-level character in a Clutch Situation could use a small die to ensure success, if the die can't roll higher than his level, it remains locked.[2]

For example, Ernar the Barbarian is 5th level, and he's gotta hit that white ape. Instead of an attack die, he declares a Clutch Situation. Now, if he rolls a 1d4, he's guaranteed success--any result is less than his current level of 5. However, for the rest of the session, that d4 is locked because he'll never roll higher than 4 on it. If he's smart, Ernar will roll a 1d6--there's a 4/6 chance that he'll succeed, but he also has a 2/6 chance of rolling his level or higher next time it's used, thus unlocking it and allowing modifiers.

Thoughts?

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1. So secret, in fact, that not even Matt Finch knows about it. Shhhhhhhh!
2. I haven't decided if carrying this restriction over from session to session is a dick GM move or not.