Arrieta and Maddux are two of the 30 untouchables. The Maddux card details just his accomplishments with the Cubs. He also has a Braves version in the set.
Maddux isn't the only player with more than one card in the set. Roy Haliday has a Phillies and Blue Jays version Pedro Martinez has both an Expos and Red Sox card,and Randy Johnson has a Mariners and Diamondback version, while Roger Clemens has cards with the Red Sox, Blue Jays, and Yankees. That means that while there are 30 cards in the set, they represent just 24 players.