Mexicana (or "Mexican Canasta") is a version of Canasta with the following variations:
Use three 52-card decks, along with 6 Jokers, for a total of 162 cards.
Each player is dealt thirteen cards.
When a player makes the initial meld for his side, he then draws the top thirteen cards from the stock and adds them to his hand.
The discard pile cannot be taken when the upcard is a seven.
A canasta of sevens is worth 1000 points.
To go out, a side must have completed two canastas, plus have laid down at least as many red threes as it has canastas.