[Psionics] New or Modified Probability Alteration abilities

[Anaraxes]

Originally Posted by TGLS

literally anything can be justified by "luck manipulation"

Yes. It's okay as a general superhero theme, like "speedster" or "wizard", but it's not in itself an ability or mechanic of any sort. Way too broad and subject to abuse.

(Telekinesis is another of my peeves in this category. The GURPS ability as written isn't terrible, but I'm sure you've known players where the word is interpreted to mean "any and all matter anywhere around me rearranges itself to suit my will, on any scale and with any degree of precision, into any desired effect", probably along with "atoms weigh way less than a pound, so I really only need ST 1 with Area Effect". The latter description as fluff is another one of those nice, broad concepts -- basically Green Lantern, only with matter instead of power ring energy -- but no, you don't get to do everything you can imagine for 30 points.)

Important principle: If you can build an ability with the existing traits, as with the Suggestion ability in the OP ("mechanically rather like the Telepathic ability of the same name"), build it that way. "Buy the effects, not the name". Note that Prince Charon does exactly that in his examples in the OP.

"Fluffwise can be thought of" is exactly that - a fun, entertaining, creative addition to the game that doesn't call for new mechanics. IMO, it's much less painful and error-prone to bend an existing ability a bit than to invent new ones. Tweak the base abilities if necessary because they have too much of some other, inappropriate fluff built into their assumptions. Put the "Probability Alteration" PM on it, and give it the Limitations that make it feel however the PA PM is supposed to feel in the game. Presto, it's a "Probability Alteration ability".

"Control Probability" as a single ability is right out. The munchkin line here is just going to drag in quantum mechanics arguments on the beeline toward Scarlet Witch-style reality alteration. Note that the Control abilities in Powers generally have very specific and limited uses. Those abilities are not the general "control" in the usual comic-book sense, where "controls ice", say, lets you make ranged blasts, melee attacks with summoned weapons, fly and hover with a special effect of sliding on an ice sheet, Bind people in place, alter temperature, kill by lowering body temperature, etc.) The Powers versions are the last-ditch method for filling in some gaps left by a suite of other abilities, not the starting point for a character. Players looking for that kind of flexibility should just pony up for the Cosmic Modular Ability pool.

So, the thread is about feel and color and fluff, not mechanics.

To get a "probability" feel, I'd try to include traits based on Serendipity, change the Malf rolls on gear if the setting has tech, or give the character some sort of refreshing Destiny Point / Impulse Buy budget, so effects like Imperial Stormtrooper Marksmanship Academy, Just a Flesh Wound, and Buying Success / Effect can happen for them. (Pricing those for a campaign where PCs don't have hero points of some sort could be tricky. But you might reverse the One Use Only rule and decide that if the original 1 CP per use is fair, then that's 1/5th of a 5-point ability that can be used once per session; buy more levels to use multiple times -- or just be content to play that "your luck has run out".) The Power Talent gives a bonus to Gambling and some Games, as opposed to "useful" adventuring skills. ("It's better to be lucky than good.") You might Afflict Total Klutz on enemies, though Cursed puts too much burden on the GM. (Also a problem with Weirdness Magnet. Suits the concept, but it's a strain to constantly invent novel, bizarre events.)