This an updated version of the original 1999 test conceived by Erwin Andreasen and Brandon Downey. Based on the 1996 paper "Hearts, Clubs, Diamonds, Spades: Player who suit MUDs" by Dr. Richard Bartle. It has retained the dichotomy, and it empoloys no randomly generated sequence. However, it does account for the imbalanced probability results (e.g. Socializer & Killer types could have had a 1 point bias compared to the Achiever & Explorer types). Also, it asks all original 39 questions including one extra (new) question to provide an entirely balanced set.
This was originally intended for a MUD (Multi-User Dungeon) audience, the precursors to the modern MMORPGs (Massively Multi-player Online Role-Playing Games). As such, you may substitute MMO when you see the term MUD on the questions during the test.
Are you a Killer? Explorer? Achiever? or a Socializer?