Four decks, sixteen aces already up, and eight reserve piles racing the stock together. One tap deals to all eight at once, no redeals, no mercy.

Leap Year Solitaire takes the old parlor game Auld Lang Syne and multiplies it by four. Instead of a single pack, you shuffle four decks together, and all sixteen aces are placed on the foundations before the first move is ever made. What remains is a race to feed those foundations from a small spread of reserve piles and a deep, unforgiving stock.
The name is a nod to how rare a clean win feels here. With four decks in play and no building allowed on the reserve, a great deal comes down to the order the stock hands you. Each time you tap the stock, it deals one fresh card to every reserve pile at once, so a card you need may be buried under three others you cannot use. Patience and a bit of luck carry the day.
There is no waste and no second pass through the stock, which keeps the game brisk. You will either steer the reserves onto the aces in time or run out of useful plays. When it works, the whole table clears in a satisfying cascade of thirteen-card runs.
If you enjoy Leap Year, try Auld Lang Syne Solitaire, the single-deck original this game grew from, or Quadrennial Solitaire, the same four-deck layout with two redeals added in.
If you run into anything odd or have an idea that would make the game better, please contact me.
Enjoy playing!
16 foundation piles: All sixteen aces are dealt here at the start of the game, one to each pile. Build up in rank from Ace to King, regardless of suit.
8 reserve piles: One card is dealt face-up to each pile at the start. Only the top card of each pile is playable, and it may go only to the foundations. There is no building on the reserve, and empty reserve piles are never refilled.
Stock: Click to deal one card to each of the eight reserve piles at once. There are no redeals.
There are sixteen foundation piles, each begun with an ace.
A card can be added to a foundation pile only if it's one rank higher than the pile's current top card, regardless of suit, so the only card that fits on a 5 is a 6, of any suit. A completed pile runs from Ace up to King.
The top card of each foundation can be moved back into play if another pile will accept it.
There are eight reserve piles, each dealt one face-up card to begin. The top card of any reserve pile may be played to a foundation, but reserve cards may never be built on one another or moved between piles.
When you click the stock, one card is dealt to the top of every reserve pile. When a reserve pile empties, it stays empty for the rest of the game.
Only one card may be moved at a time; sequences are not permitted.