This was part of a larger effort, spearheaded by WotC themselves. "Elemental Evil" was the name of the then current D&D Adventurers League season, which was running adventures from the super campaign, "Princes of the Apocalypse." The entire thing was meant as a throwback.
Three powerful entities met in the Styx Oarsman; Joretha, a dragon, Ertharex, a beholder, and Mephorda, an illithid. Each wished to prove that they were the greatest tactical mind in all of Sigil. "I am the greatest tactician," claimed Joretha. "The traps and snares within my lair translate to a clear advantage on a…
Back in the 3.5 days, I always wanted to run a landshark that had the half-fey template. From the description in the Fiend Folio: That way, I could run a Bulette with Butterfly Wings. :D