I was thinking about a new quality, but i have problems to find a solution for it. I wanted to make it similar to the superpower the black cat at Marvel Comics has. Basically it is about having bad luck if you are in close range to the character with this quality. What do you think about it? Is it more a negative than a positive quality? How could it work?

Look at the "Twist Fate" power of Great Dragons

This is possibly a little bit too much. How much would you expect this quality to be?

NPC only.

Edit: you could also take astral hazing and instead of radiating a BGC, they radiate the "Bad Luck" quality for everything inside he radius.

What would happen if this char. already has the Bad Luck Quality? I admit that i am inspired by the german novels with "Bad Luck" Walez, i don´t know if somebody here read them.

well, he would also suffer from bad luck - what else?

Hmm...possibly double "bad luck"? Instant heart attack or a simple failure becomes a critical failure ( i cannot find the correct term, damn brain). Help.....

You probably wanna make this quality affect enemies only, or one of your teammates might put a bullet in your head when things start to go south just to keep you from getting the rest of the team killed. Remember, Black Cat's ability screwed over her BFF Spiderman, it was definitely not a positive quality.

I thought about it, but if this would work like a targetable attack-power, i think the GM wouldn´t allow. Also Bad Luck-Walez had problems with his contacts because everybody that worked with him, was affected, except himself. It should be a negative quality because of the negative social effects, but because the char. himself is not affected the GM could argue about this. Also the effect is not fixed yet. Do you have a better proposal how it should work or could somebody quote how the "twist fate" power works? I can barely remember the RAW, only that the dragon can spend edge so that the edge of the char. is somehow negated. Correct? Semi correct?^^

Remember Fallout 1 and 2?
Jinxed Trait? http://fallout.wikia.com/wiki/Jinxed
You bring bad luck to others.
But, unfortunately, ALSO to yourself.
No control over it either.
EVERYBODY in the vincinity including other PC's and NPC's is more likely to glitch or critically glitch.
It's a karmic imbalance and magical residue from something done by you or your ancestors.
Everybody with LOS to the cursed one needs one less 1 on the die to glitch/critically glitch.

How bout:
Like gremlins or cursed, but for physical actions, and effects everyone nearby.

Or perhaps steal the text for Gremlins/Accident, and make it key off of Edge instead. (and maybe require a point of you want to use it instead).

Twist Fate is a bit too much. adjusting the bar on the amounts of 1's needed for glitches seems about right.

This i like. Proposed costs? 10BP? Would need to be a metagenetic quality, because of this effect, wouldn´t it?

How about when any roll (GM or player) comes up as one away from being a glitch the player is given the option to spend an edge to cause it to be a glitch. If the roll is a glitch (or augmented into one) the player is given the option to spend an edge to make it a critical glitch.

Then you can get the flavor of a character (assuming high edge) that is lucky and misfortune seems to follow those around them.

Would be a great ability this way, but if the GM would allow it?

GM:"I'll allow it!"
Minutes later, GM rolls, one away from crit, Player decides to turn it into crit.
GM:"foul!"

I think my players would kick in me the balls for making a cheap flaw or edge that messed with their dice.

Would greatly depend on the GM, the player, the game flavor, etc etc

Another perspective would be, whenever spending edge (per normal edge rules) the effect manifests as a negative effect or coincidental behavior that could be attributed to 'bad luck' to observers.

For example:
When trying to get through a checkpoint where you just flubbed your attempt, suddenly someone nearby keels over in a heart attack which distracts the officer and he waves you through.

"A wild Apirit appears and uses a LOS Version of the Accident Spell/Critter-Power!"

Yeah, this seems like it infringes on Dragon territory; it's so extra-magical.