I'm trying to figure out which trading card game is the most popular.  Can you help?
user
Sure, I have some information about trading card games on my database. Which one are you interested in?
assistant
Which ever physical trading card game is the most popular.
user
That depends a lot on the definition of “most popular.”  For example, there is a way to count which card games are most popular based on the number of US retail store sales.  It’s harder to get a good handle on the sales of card games in other countries.
assistant
Give me the name of the card game that is most popular based on US retail sales.
user
In terms of sheer sales, Magic: The Gathering is the most popular card game.
assistant
Does this trading card game still produce new cards?
user
Yes, it does.  It is also possible to build more complicated decks that consist of more cards.
assistant
I'm trying to figure out which trading card game is the most popular.  Can you help?
user
Sure, I have some information about trading card games on my database. Which one are you interested in?
assistant
Which ever physical trading card game is the most popular.
user
That depends a lot on the definition of “most popular.”  For example, there is a way to count which card games are most popular based on the number of US retail store sales.  It’s harder to get a good handle on the sales of card games in other countries.
assistant
Give me the name of the card game that is most popular based on US retail sales.
user
In terms of sheer sales, Magic: The Gathering is the most popular card game.
assistant
Does this trading card game still produce new cards?
user
In terms of US retail sales, Magic: The Gathering is still popular and there are still new sets of cards being released.  But there is a similar game called Magic: The Gathering Arena that is just card games, without all the cards you have to buy to play with.
assistant
I'm trying to figure out which trading card game is the most popular.  Can you help?