Question: Madmaze, an online video game designed by Eric Goldberg, was devoped by what American game designer and science fiction writer that is known under the pseudonym "Designer X"?

Context paragraphs:
Matt James (game designer): Matt James (born 1981) is an American game designer and a decorated veteran of the United States Army.  As a game designer, James is best known for his online and print works for the "Dungeons & Dragons" fantasy role-playing game published by Wizards of the Coast, "Pathfinder" role-playing game by Paizo, and Privateer Press.  He has also designed game content for Wolfgang Baur's Kobold Press (formerly Open Design LLC).  In 2012 James won an ENnie Award for "" and has been nominated for several Origins Awards.  In 2014, James won an ENnie Award for "".

Aaron Allston: Aaron Dale Allston (December 8, 1960 – February 27, 2014) was an American game designer and author of many science fiction books, notably "Star Wars" novels.  His works as a game designer include game supplements for role-playing games, several of which served to establish the basis for products and subsequent development of TSR's "Dungeons & Dragons" game setting Mystara.  His later works as a novelist include those of the "" series: "Wraith Squadron", "Iron Fist", "Solo Command", "Starfighters of Adumar", and "Mercy Kill".  He wrote two entries in the "New Jedi Order" series: "" and "".  Allston wrote three of the nine Legacy of the Force novels: "Betrayal", "Exile", and "Fury", and three of the nine Fate of the Jedi novels: "Outcast", "Backlash", and "Conviction".

George Gomez: George Gomez is an industrial designer, video game designer, and pinball designer who has worked for Bally, Williams, and Stern Pinball, among other companies.  He worked on the team that created the "Tron" video game, and headed the team that created "Spy Hunter".  In 1984 after the 1983 video game crash, he left Midway to invent toys at the consulting firm Marvin Glass & Associates.  After Glass he worked on numerous projects through the contract manufacturer Grand products, including the Battletech Centers and several Sega video games of the late 80's.  In '93 he went to Williams Electronics and designed several pinball machines including "Monster Bash" and was one of the lead developers of the Pinball 2000 system.  As a consultant he designed several games for STERN pinball including "The Lord of the Rings", and "Batman".  Along with his recent work in pinball, he was also one of key designers of the street basketball video game series "NBA Ballers" for Midway.

Hidemaro Fujibayashi: Hidemaro Fujibayashi (藤林 秀麿 , Fujibayashi Hidemaro , born October 1, 1972) is a Japanese video game designer working for Nintendo.  He is best known for his contributions to the action-adventure game series "The Legend of Zelda", for which he served as planner, writer and director.  Before he entered the video game industry, Fujibayashi had designed layouts of haunted attractions for Japanese theme parks.  At that time, he had considered finding an occupation involving production, and came upon a job opening from a company that developed video games.  He was fascinated with the fact that his application for employment had to include a sample of his work that would be inspected directly upon transmittal, and he became enamored with the idea of being a game designer.  Fujibayashi eventually joined Capcom in 1995, where he gained experience as planner for the interactive movie "Gakkō no Kowai Uwasa: Hanako-san ga Kita!!"  and the mahjong game "Yōsuke Ide Meijin no Shin Jissen Maajan".  Later, he became part of the company's Production Studio 1, and designed and directed the puzzle game "Magical Tetris Challenge".

Greg Costikyan: Greg Costikyan (born July 22, 1959, in New York City), sometimes known under the pseudonym "Designer X", is an American game designer and science fiction writer.

Derek Smart: Derek K. Smart is an American video game designer.  He is the president and lead developer of 3000AD, Inc., an indie game development company based in Aventura, FL.  In addition he is the president of and investor in the video game development company Quest Online.  Smart is an independent video game designer and software developer, and the creator of several video game series.

Ray Game Designer 2: Ray Game Designer 2 (also known as RGD2) is a freeware application designed for developing simple 3D computer games such as first-person shooters and third-person platformers, without learning an advanced programming language.  It was written by Emmanuel Icart of Momor Productions with the Delphi programming language.  Games created with Ray Game Designer 2 can be distributed freely or sold for profit, without paying any royalties to Momor Productions.  RGD2 can use either OpenGL, Direct3D, or its own software engine for rendering 2D and 3D graphics.  Ray Game Designer 2 uses an extremely simple syntax for creating "behaviours", code used to create simple artificial intelligence in its games.  RGD2 comes in the French and English languages, but can be translated into virtually any language by editing a few text files.  Ray Game Designer 2 is also the successor of Ray Game Designer.  The software remains unfinished and hasn't been updated since early 2002.

Steve Feak: Steve Feak (born August 1, 1984), better known by the in-game name Guinsoo, is an American game designer.  He was one of the previous designers of the popular "" custom game mode, "DotA: Allstars".  Feak attracted the attention of the game industry and Riot Games, when his mod was played by 10 million gamers.  He began this project while studying computer science at the University of Wisconsin.  Since then, Feak was employed by Riot Games as a game designer for "League of Legends", a multiplayer online battle arena (MOBA) game directly inspired by his previous work.

MadMaze: MadMaze is an online video game designed by Eric Goldberg and developed by Greg Costikyan in 1989.  It was the first online game to draw over a million players., and was playable through the Prodigy service.  The game disappeared in 1999 with the death of the Prodigy service, but with the permission from the service and the creators, fans of the game have rehosted it.

GamersGate: GamersGate AB (formerly Gamer's Gate) is a Sweden-based online video game store offering electronic strategy guides and games for Windows, OS X, and Linux via direct download.  It is a competitor to online video game services such as Steam, GOG.com, Direct2Drive, and Impulse.

Supporting paragraphs: MadMaze Greg Costikyan
Answer: Greg Costikyan