Referential Discard Clues
- The "referential" part of Referential Sieve indicates that cards next to the desired cards are clued, rather than being clued directly.
- To get an unclued card (the Target) to discard, a rank clue is given to the unclued card immediately to its left (the Focus).
- If no new cards are clued, this is instead a Reclue and is covered in level 2.
- To get a previously-clued card to discard, reveal it as trash.

When multiple cards are clued,
- The Focus of the clue is the leftmost newly-clued card.
- The Target of the clue is the unclued card to its right (without wrapping around).

Lock Clues
- A discard clue that has no Target is a Lock Clue.
- A player that is Locked is not allowed to discard any card until further information is given.
- Special rules around Locked players are explained in level 4.
