If you fan of Youtube and EN World, lately you may have come across the Dungeon Bastard aka Bill Cavalier. He is a D&D/Fantasy RPG enthusiast who since 2011 created a site and video series in which he dispenses his wisdom of all things RPG "D&D" to the world. He claims the title "Adventure Coach" and his resume on his sites explain why he is so awesome. Here is a sample of the Wisdom he so often gives....
he is kinda of an in your face curmudgeon and no nonsense approach...so be for warned.
Ironically the advice that is dispensed by the "Adventure Coach" is often munchkin-ense. It is not about the adventure or journey of a character(s), but more of what experience and awesome loot did I get for that kill?
He is highly entertaining in most of his "advice" or "learned observations/experience", it is thought provoking and worth of conversation and a few chuckles. Although I stand on many different points of opposition to his "wisdom", he is entertaining and puts himself out there which is respectable in its own merit.
Let's take his video on the Flumph. It appears the "Dungeon Bastard only has access to a few sources of information, as he wips out "ye olde" Fiend Folio circa 1979. I will assume for the sake of argument that he is using the source material because it is as "canon" as one can get. However as a counterpoint, the information on the Flumph was expanded upon in Monstrous Compendium Annual Two (1995), Dragon Magazine #246 (1998), and Misfit Monsters (2010). The Flumph like many original creatures is technically not a "Monster", but an NPC race.
In the 1998 and 2010 references of the Flumph, it has been observed to be a race of non-humans that are extra-terrestrial in origin. The beings encountered in said dungeons were most likely low level adventurers exploring and defending itself peacefully from an attacking player character party. Matter of fact he does touch on the inspiration of the race to the Lovecraft Mythos. If you know about the Flying Polyps and Mi-go, well Flumphs fit right in. Also to note that the Sesame Street "Martians" closely resemble a Flumph.
H.G. Wells "War of the Worlds" also resemble a Flumph. Also let us not forget SNK "Mars People" from Metal Slug series are Flumph like too.
Yet again, the "Dungeon Bastard" is meant as entertainment......so what doe my opinion mean after all.