- Adaptation Displacement: When the NES spinoff of Dragon Slayer II: Xanadu is the only one that leaves Japan to begin with, especially since the original version was made for a Japanese computer, this is to be expected.
- Goddamned Bats: Anything in this game that flies or leaps is particularly annoying, especially while you're trying to pull off a jumping puzzle and keep getting knocked down by a giant fly or wraith-like creature.
- Same for smaller creatures, given that you cannot attack at crouching level.
- Crowning Music of Awesome: Especially the tower/fortress theme songs and the overworld theme in the first area.
- It Is Pronounced Tro PAY: A real-world example: the official, correct pronunciation of the title is "Fa-Zanadu," but many (this troper included) believed it was pronounced phonetically, i.e. "Facks-anadu." Some still insist on the latter to this day.
- Memetic Mutation: "This is not enough golds."
- Fridge Horror: It's easy not to think about what the Evil One must have done to the dwarves to make them into monsters, but once it hits you it can seriously creep you out.
- In particular, we have the fate of King Grieve, king of the Dwarves, who as he was being transformed into a dragon-like creature, somehow managed to hide the Dragon Slayer sword within his own body to protect it from evil. And the only way to retrieve it is to kill him, and presumably cut him open.