Building runs
You build down in rank regardless of suit, but you can only move a run of cards when every card in it shares a suit. Complete King-to-Ace in one suit and the run clears itself off the board.
Two-suit Spider uses two decks of spades and hearts across ten columns. It is the version most players settle on: one suit is a warm-up, four suits is a grind, and two suits is where the game becomes a real puzzle without becoming punishing.
Play 2-suit SpiderYou build down in rank regardless of suit, but you can only move a run of cards when every card in it shares a suit. Complete King-to-Ace in one suit and the run clears itself off the board.
The stock adds one card to every column at once, and it only deals when no column is empty. That rule is why you should not leave a deal until the board is tidy.
Two decks make eight complete runs. Clear all eight to win — most losses come from mixed-suit stacks built early that can never be moved again.