Solitaire Volcano is a variant of Volcano, which was designed by Kristin Looney in 2000. In fact, Looney had envisioned Volcano as a solitaire game, before it became a multi-player game. The game is more like a puzzle and the challenges to be solved make an excellent training for regular Volcano. They help to develop the player's ability to move the black caps around, so that they'll be able to take the pieces they want to erupt.