A very popular card game that invented the collectible card game concept. It pre-dates Pokemon and still exists today. Started in 1993. Very old cards (typically black borders rather than white) can be very valuable. Common cards are practically worthless, they come in common, scarce and rare cards. There have been many, many expansion sets over the years. Better, more playable cards also tend to have more value than cards that are rarely used. I played the game from the first expansion for about 4 years after. Some very successful professional poker players started as Magic players (David Williams, for example). The game took way too much money to be competitive, so I was very casual about it. Sold off my cards long, long ago.

Black border rare card from the first expansion:

You should be able to find price guides online. There are also price guide apps.

Michael Siskin