Early levels are pretty normal, save that they have "Hawkmen, etc. 30-120" and "Miscellaneous" as entries. I'll get back to Miscellaneous in a minute. At 5th level we see Melniboneans added to the list. 6th level has the Yeti, which may or may not have already appeared in The Strategic Review #3 (dated August 1975 while A&E #2 is dated July 1975). 8th level adds Huorns to the listing for Ents, a logical extrapolation. And 13th lists Frankenstein Monster, which Gold identifies as being a D&D Golem.
But the real charm is that Miscellaneous entry, which reads as follows:
Miscellaneous = conmen, pollsters, petition passers, peddlers. stores, minstrels, revival meetings, beggars, Punch & Judy shows, etc.It's a fun bit of '70s California anachronism in the midst of a dungeon; it also emphasizes the fact that early dungeons weren't always dead serious, and a lot of the time the players were taking the piss. In Playing at the World, we find that the Golds would later do another dungeon with less anachronism than Neocarn, but it's useful to remember that the dungeons were frequently taking the piss and throwing in-jokes and modern references at the players.
One of Lee Gold's encounter descriptions involves short black-skinned humanoids that say "GNAP!" and bite at people; they bite one of the party fighters in the process, and he turns black-skinned and begins saying "GNAP!" and biting as well, until a blue-skinned humanoid decked out in red comes in and sprays tuberose on the others, and they all turn blue and regain their senses. He introduces himself as the Grand Schtroumpf (spelled schtroumph by Gold), but any child of the '80s would recognize him as Papa Smurf. This encounter is taken directly from the Belgian bande desinée Les Schtroumpfs Noirs – the first story of what would later be adapted as the Smurfs.
I don't want to recite the whole recap, just to give a flavor; there were other weirdnesses, such as a young woman who pretended to be charmed only to make off with the mule, or the mule itself which was temporarily turned into a giant spider, or the fact that the party was accompanied by a proper Rabbi's golem. I think you get the gist.
The unashamed oddness of it all, willing to have puppet shows or then-obscure references to Belgian comics, is one of the things that decades of self-serious fantasy have drilled out of most of the game. I don't think D&D should be goofy all the time, but neither should it be so dour and serious that all sense of fun is lost.