The term "Legendary Collection" has been used for various sets over the years, each containing a different number of cards:
* Yu-Gi-Oh! Legendary Collection (2009): This set contained 80 cards, including reprints and exclusive cards.
* Yu-Gi-Oh! Legendary Collection 2 (2010): This set also contained 80 cards.
* Yu-Gi-Oh! Legendary Collection 3: The Yata-Garasu (2010): This set had 78 cards.
* Yu-Gi-Oh! Legendary Collection 4: The Ancient Millennium (2011): This set contained 78 cards.
* Yu-Gi-Oh! Legendary Collection 5D's (2011): This set contained 84 cards, focusing on cards from the 5D's era of the anime.
If you're looking for a specific set, you'll need to clarify which one. Otherwise, it's impossible to give you a definitive number of cards.