Pyramid is a solitaire game where the object is to get all the cards from the pyramid to the foundation.
The object of the game is to remove pairs of cards that add up to the total of the highest card in the deck from an arrangement of cards - a pyramid of 28 cards.
When using the common French deck, Jacks value at 11, Queens 12, and Kings 13. So the highest value is 13. In the numbered Spanish deck the highest numbers are also the Kings at 12, so the pairs must add up to 12.
To set up the pyramid, deal one card face up at the top of the playing area, then two cards beneath and partially covering it, then three beneath them, and so on till you have dealt out a row of seven cards for a total of 28 cards dealt. Refer to image.
The remaining cards are placed to the side face down. This is the Stock.
To play, pairs of exposed cards can be removed to the Foundation if their values total 13 (12 if using the Spanish deck). Thus, kings can be removed immediately to the Foundation. Cards must not be covered. Thus when an Ace rests on a Queen, that Queen can not be removed.
You may draw cards from the Stock one at a time and match it with any exposed card. if no match is made the drawn Stock card is still discarded into the Foundation.
Once the Stock is exhausted and /or no more pairs can be made, the game ends.
To score, count the number of remaining face up cards in the pyramid. A perfect score is therefore zero, where all cards have been matched into the Foundation.
SOURCE: Wikipedia