Pro Shamrocks Solitaire, a free solitaire card game for the PC. Pro Shamrocks Solitaire is a more difficult version of Shamrocks Solitaire. The primary difference between Shamrocks Solitaire and Pro Shamrocks Solitaire, is that the first foundation card is chosen randomly. Like Shamrocks Solitaire the cards are dealt into 18 piles. While building the piles up or down regardless of suit, the player may not place more than 3 cards in a pile.