Greyhawk, also known as the World of Greyhawk, is a fictional world designed as a campaign setting for the "Dungeons & Dragons" fantasy roleplaying game.
 Although not the first campaign world developed for "Dungeons & Dragons"—Dave Arneson's "Blackmoor" campaign predated it by over a year — the world of Greyhawk was the setting most closely identified with the development of the game from 1972 until 2008.
 The world itself started as a simple dungeon under a castle designed by Gary Gygax for the amusement of his children and friends, but it rapidly expanded to include not only a complex multi-layered dungeon environment, but also the nearby city of Greyhawk, and eventually an entire world.
 In addition to the campaign world, which was published in several editions over twenty years, Greyhawk was also used as the setting for many adventures published in support of the game, as well as for RPGA's massively shared "Living Greyhawk" campaign from 2000–2008.
Dungeons & Dragons (abbreviated as D&D or DnD) is a fantasy tabletop role-playing game (RPG) originally designed by Gary Gygax and Dave Arneson, and first published in 1974 by Tactical Studies Rules, Inc. (TSR).
 The game has been published by Wizards of the Coast (now a subsidiary of Hasbro) since 1997.
 It was derived from miniature wargames with a variation of the "Chainmail" game serving as the initial rule system.
 "D&D"'s publication is commonly recognized as the beginning of modern role-playing games and the role-playing game industry.
In the "Dungeons & Dragons" fantasy role-playing game, the lamia is a type of fictional monster.
 The lamia is typically portrayed in the game as a creature with the lower body of a lion, and the upper torso, arms, and head of a human female.
 A less common type of lamia, the lamia noble, was depicted as having the lower body of a serpent.
 The lamia was introduced in the first edition "Advanced Dungeons & Dragons" game's original "Monster Manual" sourcebook, written by Gary Gygax and published in 1977.
 The lamia also appeared in second edition and third edition "Dungeons & Dragons".
 In the fourth edition, it was reenvisaged as a swarm of insects.
 The fifth edition disregards this and returns it to its classic design.
Blackmoor is a supplementary rulebook (product designation TSR 2004) of the original edition of the "Dungeons & Dragons" fantasy role-playing game written by Dave Arneson (with a foreword by Gary Gygax).
In the "Dungeons & Dragons" fantasy role-playing game, the giant troll is a type of monster.
Greyhawk is a supplementary rulebook written by Gary Gygax and Robert J. Kuntz for the original edition of the "Dungeons & Dragons" fantasy role-playing game.
 It has been called "the first and most important supplement" to the original "D&D" rules.
 By adding a combat system, it severed all ties with "Chainmail", making "D&D" a truly stand-alone game system.
 Although the name of the book was taken from the home campaign supervised by Gygax and Kuntz based on Gygax's imagined Castle Greyhawk and the lands surrounding it, "Greyhawk" did not give any details of the castle or the campaign world; instead, it explained the rules that Gygax and Kuntz used in their home campaign, and introduced a number of character classes, spells, concepts and monsters used in all subsequent editions of "D&D".
The Dungeons & Dragons Basic Set is a set of rulebooks for the "Dungeons & Dragons" ("D&D") fantasy role-playing game.
 First published in 1977, it saw a handful of revisions and reprintings.
 The first edition was written by J. Eric Holmes based on Gary Gygax and Dave Arneson's original work.
 Later editions were edited by Tom Moldvay, Dave Cook, and Frank Mentzer.
Jacob Franklin "Frank" Mentzer III (born in 1950), is an American fantasy author and game designer best known for his work on early materials for the "Dungeons & Dragons" (D&D) fantasy role-playing game.
 He was a performing folk musician from 1968 to 1975, and played one concert at the White House during the administration of Richard Nixon.
 He was an employee of TSR, Inc. from 1980–1986, spending part of that time as Creative Advisor to the Chairman of the Board, Gary Gygax.
 He also founded the Role-Playing Games Association (RPGA) during his time with TSR.
 He has been closely involved with the world's largest game auction at the Gen Con game convention since 1983, and is an expert on, and a major collector of, family boardgames and role-playing games.
 After Gygax was ousted from TSR at the end of 1985, Mentzer left TSR as well and helped him to start New Infinities Productions Inc. (NIPI).
 When this venture failed, Mentzer left the gaming industry, eventually becoming the manager of a bakery.
 In 2008, he closed down this business and, two years later, announced he was returning to the gaming industry as a founding partner of a new publishing company, Eldritch Enterprises.
Ernest Gary Gygax ( ) (July 27, 1938 – March 4, 2008) was an American game designer and author best known for co-creating the pioneering role-playing game "Dungeons & Dragons" ("D&D") with Dave Arneson.
 Gygax has been described as the father of "D&D".
The original Dungeons & Dragons (commonly abbreviated "D&D") boxed set by Gary Gygax and Dave Arneson was published by TSR, Inc. in 1974.
 It initially included the original edition of the "Dungeons & Dragons" fantasy role-playing game.
 Its product designation was TSR 2002.

Question: what fantasy role-playing game designed by Gary Gygax and Dave Arneson uses a giant troll as a type of monster?
Answer: Dungeons & Dragons