I remember being in a little craft store as a kid, being bored, and then finding the art instruction books (learn how to draw a tiger!) on a rack along with this. I don't know why my mother was even in there, maybe buying sewing patterns, she sewed for a while, but I do remember asking if I could have that book and being ecstatic that the answer was yes (she was always leery of the demonic nature of our beloved game, though I always reiterated "The ugly things are in the book because that's what we have to fight!")
The coloring pages were nice, with some wonderful representations of classic monsters. And I mentioned in a comment, hell, I'll quote myself:
This is no Sinbad voyage, the party meets at a tavern and plans their assault on the dungeon. Party members are lost to beholders and ettins. The dungeon is a weird underworldish place, with elemental beings. I remember one room shows a never ending battle between an army of gnolls and and one of hobgoblins (?). And in the end the remnants of the party stumble upon a door leading to a room full of treasure. The echoes of the dungeon as an abstract set of challenges drawn on graph paper is in each drawing and my ~10 year old self could sense it and was intrigued. In essence it was a new genre. I realize that, just now, in writing this, neither S&S, nor high fantasy had anything like this gang of armed men exploring hazardous, semi-random rooms.Yeah, so the old school genre of play captured in a coloring book from 1979. And after checking, the battle in the book is between hyena-like gnolls, and baboon-like hobgoblins. The fact that the artist had to choose a "style" to render hobgoblins, I think is more evidence that humanoids in the classic game are generic baddies that scale in power to give players something to whack at. Not that that is necessarily bad or good, but I think I crave a little more from my monsters.
I particularly love the album's picture of the treasure room. In writing this I'm realizing these two images would make for a perfect, iconic DM's screen. I'd probably pick the fight with the beholder as the centerpiece and then you'd have a triptych, with the call to adventure, strife, and glory of success.