To “Discards”, replace “Add an Unrevealed card of rank zero to their Discard pile.” with:-

Add an Unrevealed card of rank zero in the rightmost position of their Discard pile.

And add a new bullet point:

Reposition any card in their Discard pile to become the pile’s leftmost card.

Then after the bulleted list add:-

The leftmost card in a Reader’s Discard pile is their Power Card. At any time, the Reader may choose to act as if their Power Card were active and applied only to them.

In all card effects, replace “card in their Discard pile” with “card in their Discard pile (which is not this card)”.