I went to a 'Magic: The Gathering' tournament and was amazed at how much the cards cost

Magic: The Gathering is an American card game started in 1993. Players square up against each other using armies of fantasy monsters. It's like Pokémon mixed with Yu-Gi-Oh! but twice as complicated.

Magic: The Gathering is big, really big. So big, in fact, that thousands of fans crammed into part of the ExCeL Centre in London for the 2015 London Grand Prix. There was the main championship, side events, social events, even specialist shops and meet and greet sessions.

I accidentally attended the Magic: The Gathering championship when I was trying to get into the "Summer In The City" YouTube convention. Here's what I found: