Granted Power: You gain the power of ill fortune, which is usable once per day. This extraordinary ability allows you to force another character or NPC to reroll one roll that he has just made before the DM declares whether the roll results in success or failure. The character must take the result of the reroll.
The language needs to be cleaned up -- right now it's actually more-or-less a meaningless ability: The "before the DM declares whether the roll results in a success or failure," combined with the fact that the player can't see rolls, means it's just as likely to invalidate a failure as it is to invalidate a success. In other words, statistically, it's meaningless.
This also screws up the Luck Domain, as written. Since players don't see rolls, it also becomes statistically meaningless as written. With contingencies, it violates the rules ("...I'll invoke the Luck Domain if I fail" means that the ability is used after the DM announces success or failure.)
A contingent usage is possible: Simply specify "I will invoke the luck domain on a roll of less than 10", or "less than 12"... The DM doesn't even need to specify if the ability needed to be used: So long as they track when it is actually applied, the player can go on attempting to use it on key rolls, and the DM can just ignore it if they've marked off that it has been used that day.
That the DM can do that is very important for the Doom Domain to work: If the player specifies "reroll if it's 3 or above," and the DM says "Your ability is not invoked, but the pink mold hits you anyway," suddenly the player has a lot of info about the pink mold's attack bonus.
Here's a rewrite of both domain powers that should function in the context of LEW:
LUCK DOMAIN
Granted Power: You gain the power of good fortune. This extraordinary ability, when invoked, allows you to specify that an individual roll made on behalf of your character must be rerolled if the die result is lower than a certain number. You must take the result of the reroll, even if it’s worse than the original roll. The use of this ability must be declared before the roll is made.
This ability is usable once per day. If there is no reroll, the attempt does not count as a usage for that day. The DM is not obliged to report whether or not the ability has actually been used: If it has, the DM may simply ignore later attempts to use that ability over the course of the day.
DOOM DOMAIN
Granted Power: You gain the power of ill fortune. This extraordinary ability, when invoked, allows you to specify that an individual roll made on behalf of a target creature must be rerolled if the die result is higher than a certain number. The creature must take the result of the reroll, regardless of the original roll. The use of this ability must be declared before the roll is made.
This ability is usable once per day. If there is no reroll, the attempt does not count as a usage for that day. The DM is not obliged to report whether or not the ability has actually been used: If it has, the DM may simply ignore later attempts to use that ability over the course of the day.
...
Possibly too wordy (I have to give it to WotC, they can be pretty concise with their wordings), but hopefully the idea is clear. Some examples of the use of these abilities:
"I take a swing at the mean goblin, saying my lucky word under my breath. (Luck domain granted power, reroll if worse than 15.)"
...or:
"I aim my crossbow, whisper a brief prayer, and shoot the goblin in the face! (Luck Domain, reroll <15)"
...or:
"Reeling from the last blow, I cover my face with my hands (full defense) and curse the name of the mean goblin that did this to me. (Doom Domain, reroll >10)"
Note also that the domains specify "higher than" or "lower than," meaning you can't use the Doom domain to help another party member make a roll (as the original wording allows for.)
