Bikkelen

Scatter all five knucklebones on a flat surface in front of the player.

The player tosses one knucklebone into the air and must scoop up one or more of the scattered pieces before catching the tossed piece again.

If successful, the collected pieces are set aside and the toss repeats, gathering more pieces each round according to an agreed pattern of difficulty.

Dropping the tossed piece or failing to gather the required pieces in time ends that player's turn.

Players take turns, and whoever completes the full sequence of patterns first, or collects the most pieces, wins.