I found something.
Over at Puppy of the Month Club they are reviewing Roger Zelazny’s Nine Princes In Amber. Jon M and The Frisky Pagan have been writing about how the novel and other Amber Chronicles relate to Appendix N and its inspiration to D&D and other RPGs. Specifically The Frisky Pagan points out similarities with D&D’s Planescape Campaign and the Amber Chronicles and Jon M discusses the Amber RPG. (Good stuff click on their links)
In the comments of The Frisky Pagan’s article Cirsova points out “Amber was hugely influential on the illusionist class.“. Another older observation made by Alex in a seemingly unrelated article at Jeffro’s Space Gaming Blog points out a Zelazny creation that found its way into the monster manual “It wasn’t like he was going on about Monster Manual Rakshasa in a review of Zelazny’s Lord of Light.”
OK real quick because I am sick of looking at this and just want the info out! out! out!
Tom Moldvay took a whole bunch of inspiration from Nine Princes In Amber for his 1981 adventure X1 Castle of Amber.
First I am not the first to “discover” this but I did discover it independently for what it’s worth.
Second it is really weird that so much is taken from Nine Princes In Amber but there is no credit given even though there is credit given for Clark Ashton Smith.
Now on with what was taken. As mentioned in the InfoGalactic page there is the Grey Mist which surrounds Castle Amber and is used to force the players into the castle. Also there is the Amber family which very much resemble the nine princes and their sisters.
There is the Wild Hunt encounter with Andrew David Amber with accompanying beasts that looks like Julian’s Hunt Corwin and Random encounter while driving through the Forest of Arden. The discussion page for Castle Amber on Wikipedia mentioned this one. You will excuse me for not linking to it.
There is an altered deck of Tarot Cards some with colorfully dressed figures on them. In the adventure players are bid by Camilla Amber to draw from them effects ranging from some magic item to death. Sadly they don’t teleport players like the Trumps do. Though one of the cards give a ring of spell storing and Dimension Door is one of the spells recommended for it to hold.
There is new monster, wolf headed lupins which resemble the “wier” werewolf patrol guards that Random Corwin and Deirdre encounter in the Forest of Arden.
Speaking of lupins there is Claude Amber found in the library of Castle Amber who like Flora in her library has a dog whistle which doesn’t call Irish wolfhounds from another room to attack the players but calls lupins instead. Also for completeness there is kennel which has four pony sized hell hounds who will not attack players dressed like Amber family members.
There is a trap which I think resembles the pattern.
Though crossing it players do not teleport to Amber the way across does eventually lead to the gate which transports them to Clark Ashton Smith’s Averoigne. Crossing the trap requires players to say aloud the letters they step on or they will be afflicted with lunacy. Also spelling out one of the words as the player crosses will grant benefits much like Corwin’s memory gain when he successfully crossed the pattern in Rebma….Rebma which is Amber spelled backwards. See the letter pattern in the map above?
Castle Amber does have prison dungeons. Though you will not find a Prince with his eyes burned out, there is mad Gaston Amber with a paint brush painting a highly realistic depiction of the moon on the far wall of his cell. His cell which is unlocked. Pretty sure he is Dworkin.
Lastly there is Stephen Amber who is the dad of all the Amber’s and like Oberon is dead but not really dead.
There is more which could be from other books in the Chronicles of Amber series. For example there is a unicorn which in Nine Princes in Amber only appeared as symbol for Oberon and might show up in later books.
Beyond the Nine Princes of Amber X2 Castle Amber is a hot mess of pulp references. As mentioned there is the Clark Ashton Smith stuff as well as an Poe encounter with an Amber sister who is buried alive by her brother and calls out to him. There are Rakasta, cat like humanoids, which Alex pointed out come from Zelazny’s Lord of Light and there is the Brain Collector or Neh-Thalggu which looks to me comes from Lovecraft.
There could be tons more which I missed. X2 Castle Amber is perhaps the most Appendix N of supplements I have ever seen and perhaps is the best TSR published example of what Jeffro calls Kitchen Sink. For X2 Castle Amber Tom Moldvay really went all out in drawing from literary roots to flesh it out.
You might even say he grabbed Appendix N by the Rakasta for this one.