Rumo and his Miraculous Adventures (Rumo for short) is a book by Walter Moers set in Zamonia, the setting for The 13 ½ Lives of Captain Bluebear and The City of Dreaming Books. It revolves around Rumo, a wolperting (an intelligent, bipedal, horned dog), after he is kidnapped by cyclopean pirates. Following his escape from them, he sets off on a journey to find 'the silver thread' that will lead him to true love, but is waylaid repeatedly, most importantly when almost everyone he knows is kidnapped and taken to the hellish underground Netherworld, which he must rescue them from. Along the way he picks up several friends, including Dandelion and Krindle, the talking sword possessed by two very different spirits, Voltozan Smyke the shark grub, and Urs of the Snows, another wolperting and talented chef.
The book provides examples of:
Achilles' Heel: The Demonocles' is their tongue, which has a complex cartilagineous structure connected to their spinal cord. Hyronically, also The Lunawraith, who are supposedly intangible, and even General Tick-Tock's virus have one equivalent weakness. You'd ask yourself how can a virus have a spinal cord, but given the massive amount of weirdness you will have been exposed to by then, it won't be too much.
Always Chaotic Evil: As always, there are some Zamonian races who lack any redeeming qualitites. The Demonocles are probably the worst, though — their entire culture, such as it is, revolve around taking prisoners to eat them alive, making sure their victims stay alive for as long as possible because they like their food to struggle. Completely lacking in empathy unless it involves breaking a Demonocle's tongue; that's just taking it too far, they can't even begin to see anything wrong with this.
The Atoner: Volzotan Smyke has traces of this in the latter parts of the novel, when he performs heroic deeds largely in an attempt to make up for past misdeeds.
Beware the Nice Ones: Urs is a friendly and talkative soul who doesn't care much for fighting and would rather spend his time cooking or eating; he's viewed as a bit of a pushover by Rumo. Later on, however, he proves himself as one of the most formidable warriors in Wolperting: His reluctance to fight is for personal reasons, not because he isn't any good at it.
Genius Bruiser: Most Wolpertings are formidable fighters, but very intelligent, they are very talented chess fanatics for example. The mayor of wolperting is trying to support an image of wolpertings are more than just fighters, which is what they are known for throughout Zamonia. Rumo, however, is not the brightest wolperting in the world.
Ushan de Lucca dies so that Tick-Tock can't reach the other fighters to kill them.
Also the skeletal yetis prevent Gornab's conquest of the surface by collapsing a cave roof on top of themselves.
I Have This Friend: The protagonist asks The Mentor what his friend Urs is supposed to do after falling in love with a girl. He's a Bad Liar and several times says "I" instead of "Urs". The mentor is nice enough not to mention — at least at first, but he does eventually lose patience, especially since Rumo's situation was the talk of the town anyway and everybody knew about it.
Nested Story: There are lots and lots and lots of stories-within-a-story in this book, and often there are stories within the stories-within-a-story. This is even lampshaded by Smyke when he tells Rumo the story about the siege of Lindworm Castle. Since Rumo at this point is very young and knows next to nothing about the world, Smyke needs to include several other stories in order to explain the events of his primary one. At one point he remarks rather dryly that this is the third consecutive story he's had to tell, and he hasn't even gotten to the part about the siege yet.
Only Sane Employee: Friftar. This means even more since he has an Ax-Crazy boss who is able and allowed to kill people with his own teeth if he likes it.
Our Homunculi Are Different: They are created in Hel from a massive vat and they are a mash-up of the various creatures thrown into the vat.
Our Monsters Are Weird: At one point they fight a 7-foot long blind albino rat with tentacles. This is probably the least odd creature they encounter in Netherworld.
The Plague: General Tick-Tock has one engineered, as an ultimate weapon.
Proud Warrior Race: Wolpertings are very talented fighters, which is why fighting is an important part of their culture and education. They don't seem to think slaughter is their life's calling, though, unlike the demons and the yeti, and also devote themselves to other trades and disciplines.
Red String of Fate: It is called the silver thread, and can actually be perceived by wolpertings from their early childhood; at that point they don't even know it's a romantic thing, they just have the notion that if they follow the silver thread to its source, something wonderful will be at the other end. Unfortunately, Rumo knows nothing about relationships or even what girls are until he arrives in Wolperting, so it's not as much use as you might think. Also, the trope is played with a bit, because while following the silver thread does lead to the wolperting's soulmate, it's by no means a given that it'll actually work out in the long run — as exemplified by Urs, whose soulmate eventually left him.
Running Gag: To Rumo's steadily increasing annoyance, he shares his name with a popular Zamonian card game, and (with a few exceptions) every single person he introduces himself to will immediately mention this. Towards the end, he just snaps "yes, like the card game!" as soon as they open their mouths.
The Starscream: Friftar planned to take over Hel's throne and start his own dynasty by killing Gornab. And he would have succeeded, if it weren't for the Copper Killers' conveniently-timed intervention.