Las Vegas Boulevard, labeled the first expansion for Las Vegas, includes several modules that players can use individually or in combination, specifically:

Eight dice in two new colors to allow for up to seven players.
A purple die for each player that allows you to remove an opponent's or own die when placed (with enough purple dice to have up to eight players).
A large die in each color, except purple, that counts as two dice when determining who scores at a casino.
Two white dice to play the basic variant with up to 7 players.
Rules for playing a solitaire version of the game.
Rules for playing a variant of the game.
Bills worth $100,000.
One-shot action cards, with each player receiving one such card at the start of each round.
A new, seventh casino; on a turn, a player can place all the dice he rolled of a single number in this casino, but then no more dice of this number can be placed in this casino by any player.