Kid sister's asset side reads:

E:Commit 1 foundation: Ready a committed non-character card. At the end of this turn, add this card and the readied card to thier owner's momentum.

1) Am I able to use this on my opponent's committed founations to put them in thier momentum at the end the turn?

2) I assume I am only able to use this on committed foundations, and not ready ones correct?

#1. Yes

#2. Yes, a ready card can't be readied.

rC( ) said:

*STAMP*

another question, not that i am sure this would ever come up...but maybe....

Since the "commiting" is part of the cost, and the "readying" part of the effect, you could commit a foundation in your staging area for the cost, and then ready it for the effect, correct? (idk say you only needed one momentum and your opp has no committed foundations)

Well Mr Mazzurco, that would work, because you have to pay all costs before you can resolve the abilty. So you may ready the card you commited for the cost. However you would end up with 2 momentum not 1, if you only needed 1 then i would suggest readying an opponents foundation where possible.

babelfish666 said:

*STAMP*

One player shocked me with his Promo Rera deck, and played lots of attacks in one turn. He used Kid Sister's E on all of them, readied most of my staging area, and threw it all into my momentum at the end of the turn. Ouch.

The moral of this story is: don't judge a book by it's cover, or in this case, by it's stats.