The rules in Sections C and F can affect what cards may be legally discarded. The other cards are odd. As the player discards, the top card must be placed so as to conceal the other cards on the stack. Players failing to do this should be chastised. F. Discarding Sevens and Jokers.
Sevens have special properties.
They may always be discarded, and the discarder may use it to change the parity of the stack. Any other specifications the player makes will have no effect on the status of the stack. The next player uses the discarding rules of the previous section, except that the parity may have been changed if the top card is a Seven. If no declaration is made then the stack behaves exactly as if the Seven was invisible. Jokers can be used to completely alter the status of the stack.