— Jake Chambers
Blaine the Mono was a sentient monorail that went insane over the course of its long lifetime. He became suicidal and attempted to kill Roland and his ka-tet in his suicide, but was ultimately defeated.
Blaine's brain was housed in a series of dipolar computers beneath the city of Lud. His original purpose was to ferry passengers away from Lud and had stops in Candleton, Rilea, The Falls of the Hounds, Dasherville, and Topeka.
He was described as being colored pink and was over "two wheels long". He had a top speed of over 900 miles per hour and produced a sonic boom. Even though he existed in Mid-World, he knew of other worlds, including New York City. He enjoyed doing John Wayne, Humphrey Bogart and Jimmy Stewart impressions.
Blaine assisted in his sibling train Patricia's suicide by removing some of her programming.
Blaine also had a rogue part of his brain that was dubbed "Little Blaine". Little Blaine appeared to be more sane than "Big Blaine" and tried to help Roland, but was not able to help very much. Little Blaine was afraid of Big Blaine, and wanted to help stop him, but all he could really do is tell the ka-tet not to enrage him.
Role in the Dark Tower Series
In The Waste Lands
Blaine was first mentioned in Jake's final essay, My Understanding of Truth, where Jake wrote that "Blaine is a pain and that is the truth." Blaine was also foreshadowed by the book, Charlie the Choo-Choo, where Charlie was a seemingly friendly train but had a smile that "couldn't be trusted."
Susannah and Eddie discover Blaine in the Cradle of Lud. When Roland and Jake reunited with them, Blaine set a sequence in motion to release nerve gas on Lud. The ka-tet was forced to solve a riddle before they were allowed to board Blaine. Susannah, using Detta's memories, was able to solve it just before the gas was released. Blaine planned to kill them anyway in his suicide, but Roland was able to convince Blaine to let them live if they beat Blaine in a riddling contest.
In Wizard and Glass
Wizard and Glass picks up where The Waste Lands left off, the riddling contest between Blaine and Roland's ka-tet. Blaine answers every riddle posed to him without pause. He answers all of Roland's Fair Day riddles and all of the riddles from Jake's book, Riddle-De-Dum. Eddie is the one who finally stumps Blaine with the jokes that Roland had previously declared "unworthy".
Blaine's mechanical brain is fried from the effort involved of him answering the jokes. The rest of his body continues to slide along the tracks and crashes into the station in Topeka. Fortunately, he had slowed down enough for the ka-tet to survive the impact.
Blaine the Mono's Riddling Competition
Preparing for the Trip
The riddling contest, and hellish ride, with Blaine the Mono begins when Eddie and Susannah reach The Cradle of Lud. When they awake Blaine one of the first things he says is "Ask me a question" and threatens to electrocute them if they do not. Susannah solves this first one by using Jake's riddle he had asked by the fire that had gone unanswered: "There is a thing that nothing is, and yet it has a name. It's sometimes tall and sometimes short, joins our talks, joins our sport, and plays at every game." Blaine quickly responses with "a shadow." Eddie almost put theirs lives in jeopardy when he in turn asks Blaine "When is a door not a door?"
Blaine agrees to give the ka-tet a ride out of Lud when he learns that Jake has a book of riddles and that Roland knows many as well. Blaine then disappears to find the other half of the ka-tet and leaves the gunslingers with another riddle: "You have to prime the pump to get me going, and my pump primes backwards." Blaine finds Jake and Roland in Tick-Tock Man's headquaters. As a test to prove who they are, he requests a riddle from the gunslingers' Dinh. Roland asks Cuthbert's favorite riddle, "What's better than all the gods and worse than Old Man Splitfoot? Dead people eat it always; live people who eat it die slowly?" and after Blaine gives the answer of "nothing" they all race back to The Cradle.
Once everyone is back together Susannah solves Blaine's riddle, with the help of Detta Walker, by pressing all the prime numbers between 1 and 100 backwards on the control box at Blaine's gate. Right as the gunslingers get aboard, Blaine releases poisonous gas.
Trip to Topeka
Right at the start of the ride Blaine makes it clear he means to crash in Topeka, killing himself and the gunslingers, and wants them along for the ride as entertainment. Roland stands up to Blaine and refuses to start riddling at Blaine's command. Instead he presents the idea of a Fair Day-styled contest in a hope to save the ka-tet. During this time Roland and Blaine swap riddles. Roland asks "What is the difference between a grandmother and a granary?" Blaine quickly answers "One is one's born kin and the other is one's corn bin" and compares it to "What is the difference between a cat and a complex sentence?", to which Jake answers "A cat has claws at the end of its paws, and a complex sentence has a pause at the end of its clause." With the rules of the game agreed on the contest begins.
In the first round Roland wants to test Blaine and has the ka-tet take turns. He has each person step forward and ask one riddle each time increasing in difficulty, Susannah is first, followed by Jake, then Roland with Eddie last reading from the book.
- Susannah: "What has four wheels and flies?" The Town Garbage Wagon.
- Blaine scorns her for this riddle calling it a "childish" riddle.
- Jake: "What can run but never walks, has a mouth but never talks, has a bed but never sleeps, has a head but never weeps?" A river.
- Blaine tells Jake he enjoys this riddle much more than Susannah's and that she could learn from him.
- Roland: "What has four legs in the morning, two legs in the afternoon, and three legs at night?" A human being.
- Eddie: "No sooner spoken than broken. What is it?" Silence.
- Blaine puts down Eddie, saying he knows nothing of silence.
At this point they realize that their initial strategy is not going to work and Roland takes the helm with his multitude of Fair Day riddles and plans on having Jake finishing up with "Riddle-De-Dum."
- "Feed me and I live. Give me drink and I die. What am I?" Fire
- "I pass before the sun, yet I make no shadow. What am I?" Wind
- "This is as light as a feather, yet no man can hold it for long." One's breath
- "If you break me, I'll not stop working. If you can touch me, my work is done. If you lose me, you must find me with a ring soon after. What am I?" The human heart
- "What may go up chimney down but cannot go down a chimney up?" A lady's parasol
- "We are very little creatures; all of us have different features. One of us in glass is set; one of us you'll find in jet. Another you may see in tin, and a fourth is boxed within. If the fifth you should pursue, it can never fly from you. What are we?" The vowels: a, e, i, o, and u
- Roland mentions this is a riddle created by his old teacher Cort and Blaine cuts him down instantly saying it was actually created by a man named Jonathan Swift from London.
- "Where may you find roads without carts, forests without trees, cities without houses?" On a map
- "I have a hundred legs but cannot stand, a long neck but no head; I eat the maid's life. What am I?" A broom
- Another variation ends with "I ease the maid's life" but Blaine prefers Roland's to his own.
- "Cannot be seen, cannot be felt, cannot be heard, cannot be smelt. It lies behind the stars and beneath the hills. Ends life and kills laughter. What is it?" The dark
- "This thing runs but cannot walk, sometimes sings but never talks. Lacks arms, has hands; lacks a head but has a face. What is it?" A clock
- "What builds up castles, tears down mountains, makes some blind, helps others to see?" Sand
- "What lives in water, dies in summer, and grows with its root upwards?" An icicle
- "Man walks over; man walks under; in time of war he burns asunder?" A bridge
- "What has eyes yet cannot see?" Blaine points out this one has four answers: needles, storms, potatoes, and a true lover
- "I occur once in a minute, twice in every moment, but not once in a hundred thousands years. What am I?" The letter M
- This one is actually never answered during Blaine's riddling contest.
With this last riddle Roland retires and has Jake ask riddles from his book, in hopes that was the reason it was brought into Mid-World.
- "In a tunnel of darkness lies a beast of iron. It can only attack when pulled back. What is it?" A bullet
- "Walk on the living, they don't even mumble. Walk on the dead, they mutter and grumble. What are they?" Fallen leaves
- "I am emeralds and diamonds, lost by the moon. I am found by the sun and picked up soon. What am I?" Dew
- "With no wings, I fly. With no eyes, I see. With no arms, I climb. More frightening than any beast, stronger than any foe. I am cunning, ruthless, and tall; in the end I rule all. What am I?" The imagination of man and woman
- "Out of the eater came forth meat, and out of the strong came sweetness." The eater is a lion; the sweetness is honey, made by the bees that hived in the lion's skull.
- Blaine also correctly identified this riddle as the one told by Samson in the holy book known as "Old Testament Bible of King James."
With nothing left to try Jake sits down, defeated.
Eddie Sets the Devil on Fire
While Roland and Jake attempt to puzzle Blaine, Eddie sits quietly in a trance searching for the question that will let them live. His mind keeps bouncing between the night on the road to Lud when Roland had told Jake a riddle to calm him down and a statement his brother Henry had once made; "when Eddie is in that fuckin zone, he could talk the devil into setting himself on fire." Eddie finally realizes what he needs to fight Blaine with, that everything balances on the meaning of "good" riddles. That night at the fire Roland had shown his disgust with Eddie when he told a joke and played it off as a riddle, Blaine had done the same thing early in the game.
- "What has four wheels and flies?" The town garbage wagon
- Blaine insults Eddie since this "silly" riddle has already been asked once before.
- "When is a door not a door?" When it is a jar
- This is the first time Blaine clearly stumbles on an answer.
- "The big moron and the little moron were standing on the bridge over the River Send. The big moron fell off. How come the little moron didn't fall off, too?" Because the little moron on was a little more on
- Blaine refused to answer this one at first, until Roland reminded him that would make him the loser. Blaine starts to go crazy with this one as he starts to take longer to answer while making loud clicking noises, the lights flicker, the cabin rocks and the walls go in and out of transparency.
- "Why do the police lieutenants wear belts?" To hold up their pants
- "What's Irish and stays out in back of the house, even in the rain?" Paddy O'Furniture
- "Why do people go to bed?" Because beds won't come to them
- "What is the greatest riddle of the Orient?" Many men smoke but Fu Manchu
- "Why did the dead baby cross the road?"
Blaine nevers answers this last one; in fact, it kills him. His map screen busts into flames, he screams a string of nonsense and for good measure Eddie shoots the screen six times. With that the hellish ride on Blaine the Mono comes to a stop (crash) in Topeka.