Ok. i believe the text on Kisheri is "After your opponent reveals a card from their hand"

How about things like bitter rivals played by your opponent (E, Reveal your hand:) or if the opponent Forms with King (F, reveal your hand:)

2 Qs...

1. Is it only revealed from card EFFECTS, or is cost ok too? (as long as not "cost" to play a card/reversal)

2. Is it only when ONE card is revealed, or does it trigger if the whole hand is revealed?

Smazzurco said:

Kisheri's response is actually:

R (5+): after your opponent reveals any number of cards from their hand, they must discard 1 card.

1) effects and cost both trigger. reversal will trigger as well because the cost of a reversal is to reveal it. just not playing cards from their hand.

2) any number of cards.

hopefully it will become when they reveal due to effects of a card

Why would it not work against Reversal? Reversal is a response ability, so think about it this way: "R Reveal this card from your hand: stuff".

It WOULD work against costs and effects because it doesn't specifically state "due to a card effect", but Hata has ruled that it's only from card effects, because you would be forced to discard every time you try to play a card otherwise, since you start the card playing sequence by revealing the card you want to play, then moving it to limbo.

(Of course, this will need functional errata... but the card hasn't even been released other than, I think, as a participation prize somewhere, so it's not exactly the most urgent situation as long as it's ruled correctly for the moment.)