Klondike empty columns: three checks before moving a King

A King is the entry ticket

In Hitoiki Arcade’s Klondike, an empty tableau column accepts a King alone or a legal alternating-color descending group whose first card is a King. It cannot accept a Queen alone or a group beginning with a Queen. A visible King is not enough: every card included in its selected group must also satisfy the group rule.

If the King is in the waste, it must be the front card. A King visible behind another card in draw-three is not yet selectable. Count accessible Kings as well as empty spaces. A gap with no accessible King cannot immediately become a new home for a Queen group.

Check what the King is covering

Consider column A with one face-down card followed by face-up black King, red Queen and black Jack. Column B is empty. Those three face-up cards form a legal group. Move the group beginning at the King into B, and the hidden card remaining in A turns face up. You do not know its rank beforehand, but you have gained one card of information.

Now compare column C containing only a face-up red King and black Queen. Moving that group to B leaves C empty without uncovering anything. The same group has changed columns, and the number of empty columns stays the same. This need not be harmful, but do not count it as progress merely because an empty space was filled.

Look at the Queen you want to place next

A front black King accepts a red Queen; a front red King accepts a black Queen. The word front matters. If the King already has a Queen and Jack in front of it, moving that whole group does not create an exposed King landing place. Always inspect the front card of the resulting column.

Suppose the front waste card is a red Queen and you can move a single black King into the empty column. You can then put that Queen on the King. In the earlier black King, red Queen, black Jack example, the resulting front card is the black Jack. A second red Queen cannot be attached there directly. The King’s color alone is insufficient to describe the next move.

Plan a short sequence, not an isolated move

Describe a candidate as a short sequence: move the King group, expose the hidden card, then look for a legal destination for the newly revealed card. The last step may have to wait because its rank is unknown. A waste-Queen plan is more concrete: check in advance that the King move really leaves a front King to receive it.

There is no fixed rule that one empty column must always be preserved. A Kingless gap is a waiting space, and its value depends on the legal King move you can use there. Compare whether each candidate improves access to hidden tableau cards or to the waste. A move with an identifiable next purpose is easier to evaluate than one made simply to tidy the layout.

A legal move is not a winning promise

Legality can be checked exactly: the group begins with a King, all its cards are face up, and they descend in alternating colors. Whether the move leads to a win depends on the other cards and the hidden cards that will appear later. Keep those two questions separate instead of treating every allowed King move as a recommendation.

Undo can help you compare alternatives and notice which King exposed a useful card or received a particular Queen. Restarting the same deal gives a longer comparison from the opening. These are learning tools for understanding consequences; efficient use of empty columns does not guarantee victory in an arbitrary random deal.

Questions and answers

Can a Queen enter an empty column?

Not in this Klondike implementation. You need a King or a legal group starting with a King.

Is moving a King to an empty column always progress?

It may simply relocate a column if it reveals no hidden card and opens no new destination. Check the resulting moves.