In 1981, Chaosium published Griffin Mountain, a RuneQuest supplement set in Glorantha written by Rudy Kraft, Jennell Jaquays[a], Greg Stafford, and Sandy Petersen.

Although Demesse thought the material was essentially identical to the previous Griffin Mountain, he though the new streamlined rules system of 3rd edition RuneQuest made this a more playable product.

"[7] In the September 1986 edition of White Dwarf (Issue #81), Robert Neville had a few quibbles, complaining about the changes made to the names of monsters and deities in order to move the material out of the world of Glorantha.

"[9] In the October 1987 edition of Dragon (Issue #126), Ken Rolston lamented the loss of the world of Glorantha, but admitted that "it is with resigned enthusiasm that I salute the adaptation of the Gloranthan Griffin Mountain material to more generic fantasy conventions."

Rolston applauded the quality of work, saying, "The campaign background material, game-master staging notes, minor encounters, and scenarios are exceptionally well-done.

He also liked the short adventures that were included, commenting that "The best things about the scenario resources are their brevity and variety - perfect for an evening’s entertainment, easily reviewed and understood by the GM, with good maps and simple text descriptions."

"[2] In Issue 5 of The Games Machine, John Woods believed that the original Griffin Mountain supplement had been "one of the best adventure packs ever for any system", so he was pleased to see the new edition.

He heartily recommended Griffin Island, saying "Anyone who wants an FRP system with both realism and playability, and which can be readily adapted and expanded to fit in with almost any fantasy world, need look no further."

"[11] In his 2023 book Monsters, Aliens, and Holes in the Ground, RPG historian Stu Horvath noted, "Removing the Gloranthan lore carves out the campaign's uniqueness, rendering it indistinct from other products of the period.

Horvath concluded, "The reprint did one thing right, though ... [providing] a large, mostly blank, map of the island for the players to fill in as they explored, complete with (possibly erroneous) annotations from previous owners.