ASDFer is an archetype created by 1234cookie, based of his friends on ASDF forums. It was origionally only for member of the roleplay thread, "Quest for the Magical Cookie" but is now planned for expansion into other notable members such as moderators.
Most ASDFers are LIGHT attribute and Warrior-type, with the exception of ASDFer - Gamma, who is a Spellcaster.
ASDFer do not have too many cards specific to them at the moment. An ASDF deck would use lots of cards specific to one monster, like Teleportation or Aura Power.
Other than ASDFers, there is also a JKL;er and a Chaotic Neutral, which are relied on for ASDFer - Shai'tan's effect.