I've read the Silmarillion several times, read through [0] and [1] each once, and I still mostly got tripped up on all the kings of Gondor who sound apparently a lot like antidepressants (I got 18/24).

[0] https://www.amazon.com/Introduction-Middle-Earth-Published-W... [1] https://www.amazon.com/Languages-Tolkiens-Middle-Earth-Compl...