Several of Lu Chen's foundations add themselves or other foundations to the card pool.
Pillar of Heaven reads:
"R Add this card to your card pool: After your attack played as a reversal deals damage, add the top card of your opponent's deck to their card pool face down.
Lu Chen R Discard 1 momentum: Before you clear this card from your card pool during the End Phase, add this card to your staging area ready."
However, according to the current Advanced Rules, I believe any foundations in the card pool are added to the staging area during the end phase, unless they were played as blocks. So Pillar of Heaven (and any other foundations added to the card pool) will always return to the staging area at the end of the turn.
That being the case, what purpose does the Lu Chen R serve?
Relevant AR section:
"9.3 Any card played as a block will be placed in the discard pile.
9.4 Any face down card in the card pool will be placed in the discard pile.
9.5 Any action card will be placed in the discard pile.
9.6 Any asset will be moved to the staging area.
9.7 Any foundation that was played will be moved to the staging area."
EDIT: Just took a close read. 9.7 says "Any foundation that was played" and I guess in this case the foundation wasn't played... But I couldn't find anything about cards that were added to the card pool without being played. How do we clear them?