1. Ok, so no officially-sanctioned way the mechanic works, then.
We like to keep certain things open to table rules.
2. I meant multi-die activations, but I notice now that Jinx says "costs one less die", so I assume that means multi-die activations are possible. I didn't see any charts in the book, just the one set of examples of things that could happen to a PC at each die level, so I guess it's just up to the GM to determine an appropriate result. I was just worried that I'd say, "I want to spend 3 dice to activate his critical failure", and the GM could respond, "okay, his initiative round drops by 3" or something similarly useless without any recourse. Again, I guess it's up to the GM.
You can apply the same rules to villains in this case as heroes. Puma's right, though - the GM gets to determine the exact effects and whether two or more dice (or, in fact, whether any
dice) may be spent to activate criticals.
3) If you use Fortune Favors the Bold (+2 to action die rolls) as a simple benchmark, Lady Luck's Smile seems kind of underpowered. Best-case, with d4 action dice, you still end up gaining an expected value of only +1 2/3, and it drops to about +1 once you go to d6 action dice, and less beyond that. Is this just a natural diminishing returns feat that you take to try to squeeze every last bonus out of action dice in a focused build? It seems like it should also grant an additional +1 to be balanced relative to FFtB (in which case it would be more useful for d4s like the bonus dice, but less useful for large dice). Similarly, Fortune's Fool seems strictly worse than Fortunate, since the maximum number of dice you can earn is capped at what you get automatically from Fortunate. Am I missing anything?
The effects of these three feats are very different, and while they're not precisely balanced against one another statistically, they serve very different play styles...
Fortunate statistically diminishes as your character levels, though not by much, and not universally (a bonus die used for anything other than boosting a result is just as useful no matter what level you are).
Fortune Favors the Bold also statistically diminishes as your character levels, but always guarantees you a minimum action die result when rolling, which can be especially useful with certain boosting and ability combinations.
Lady Luck's Smile again diminishes statistically (noticing a trend?) but operates a lot like an increased threat range, making every die roll more exciting.
So it really depends on what you're after while building your character and playing the game.
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