Arno Nickel is a well-known German chess publisher and one of the world's leading grandmasters in correspondence chess. He is living in Berlin, which is also the place of his publishing company Edition Marco. Since 1983 he has been editing the German "Schach-Kalender", a pocket-calendar with about 1200 biographical player entries each year and a lot of information, stories, anecdotes, statistics, pictures and other things each year. From 1991 until 1994 he edited the "Schach-Journal" together with Alexander Koblencs, former trainer of Mikhail Tal. In 1996 he published Robert Hübner's famous book "Twenty-five Annotated Games". 2009 he published another book by Robert Hübner, this time in German language, with the title "Der Weltmeisterschaftskampf Lasker-Steinitz 1894 (UT:)und andere Zweikämpfe Laskers". His latest projects were a posthum edited book from Rudolf Reinhardt on "Aaron Nimzowitsch 1928-1935", a book which later has also been published in English by New in Chess, and a book from Michael Dombrowsky, titled "Berliner Schachlegenden. Erinnerungen und Portraits aus der Zeit vor und nach dem Mauerbau".
In a correspondence match lasting many months, he won two games and drew a third against Hydra, the most powerful chess supercomputer in the world at that time (2005). Nickel, who achieved his grandmaster title in the era before GM-level chess computers, was allowed to use weaker personal computer chess engines to help him decide on his moves in this match. Hydra also received limited assistance from human chess experts and programmers, especially in choosing its opening book moves.
Since 2005 Nickel has been promoting Freestyle Chess, a new kind of online chess competition with computer-assisted play, where almost anything is allowed, also help from other players. He was a co-organizer of the series of PAL/CSS Freestyle Tournaments in 2006-2008, where teams of classic chess masters and grandmasters competed against correspondence chess and computer chess specialists as well as amateurs armed with computer chess engines. An unassisted human or unassisted computer playing alone has never won one of these events; the top prizes have always gone to human/computer teams (often with multiple humans and multiple computers on each team). Since 2008 Nickel promoted the Infinity Chess project, which is ocated in Abu Dhabi. Amongst others Infinity Chess has dedicated itself to Freestyle chess, while it basically supports four play modes: human, engine, centaur and correspondence chess. In 2014 Infinity Chess performed a "Freestyle Battle" donating $ 20'000 USD prize fund. This was the longest and hardest contest in Freestyle Chess ever, performed as a round robin tournament with 30 of the strongest players in this kind of chess. Infinity Chess Freestyle Battle 2014 2015 InfinityChess is holding a "Team Cup" in computer chess with 24'000 € prize fund.
In March 2007 Arno Nickel beat ICCF World Champion Joop van Oosterom in their correspondence game from 21st WC Final. Yet, van Oosterom won the Final and became a second time Correspondence Chess World Champion. Nickel finished fifth out of 15 finalists.
In 2006 Nickel started his first online correspondence chess game against the "World", i.e. the combined efforts of the users of ChessGames.com. Nickel resigned this game on January 11, 2007 after White's 41st move. A rematch started on August 25, 2008, which ended in a draw on February 25, 2009. About 1500 users participated in each of these exhibition matches. .
On February 16, 2009 Arno Nickel won the Simon Webb Memorial, a category 15 correspondence chess event with 13 grandmasters.
In the ICCF Champions League top group A, season 2007-2009, he achieved the best result on board 1.
In 2011 Nickel won the gold medal with the German olympic team in the Final of the 17th ICCF Correspondence Chess Olympiad. He achieved 8 out of 12 and the best result on board 3. 
With an Elo of 2632 his ranking in the ICCF rating list 1/2015 is No. 13 of the World.
Nickel published various articles on computer chess, correspondence chess and chess history. His latest series in the German magazine Schach in 2014 discussed the problem of increasing draw rates in correspondence chess due to assistance by powerful computer hardware and software (so-called 'chess engines'). He highly recommends to adopt the old idea from Emanuel Lasker, as also promoted by Richard Réti, to change the draw (chess) rules by counting stalemate as 3/4 point for the player who stalemates the opponent, which means achieving a 'stalemate win'. Accordingly a loss by stalemate would be a 1/4 point. Nickel argues, this rule refers to ancient traditions in chess and would bring back creativity and complexity to the game in the era of computers. He proposes to call it Lasker Chess in contrast to Fischer Chess and Capablanca Chess.