What is Netdecking?
1.
The process of stealing a tournament winning TCG/OCG/CCG decklist from a discussion forum and replicating it. Implies a lack of creativity and desire to do nothing other than win in the player.
Clans are notorious for this, particularly like the lamers who make up the Yu-Gi-Oh clan "g3n3s1s".
Go to any tournament for this type of game and you'll see a lot of it. The winning decks will always have a great deal of cards in common.
2.
The process of a card for card copying of a winning decklist from a collectible card game that was posted on the internet. If it wasn't posted online, it's not netdecking.
Clans who do this are usually very intelligent -- they know it's the best way to win. Those who play games for a profit live and die by this.
ExMinionOfDarkness netdecked Eric Wu's Zombie/Chaos deck to qualify at the 4-10-05 Butler, PA Regionals.
