The seventh and final installment in The Chronicles of Narnia and the seventh book chronologically. Seven years (on Earth) after the events of The Silver Chair, Jill and Eustace are summoned back for one last adventure, to aid the current King of Narnia against the treachery of the ape, Shift, and his quasi-Arabian Calormene allies.
This book provides examples of:
Action Girl: Jill has developed into one of these, being even better than Tirian at woodcraft, and a reliable archer.
Also, the intended Aesop behind Susan's "betrayal," which becomes clearer upon reading the author's nonfiction writings.
And the Adventure Continues: The ending tells the reader that the previous books were just the covers of the true stories, and that the true stories will continue on forever and ever, each chapter better than the last in the true Narnia.
Bitter Sweet Ending: Even if the children are now happily living in Aslan's country, the realization that they had been mangled corpses on some train platform for the better part of the book is still jarring to the reader. This is because The Last Battle has the same type of optimism found in the Book of Revelation — the end of this world is just the beginning of a truer existence; if you don't buy it, the ending might come off as very dark indeed.
Bread, Eggs, Breaded Eggs: Shift claims that the Narnian Aslan and the Calormene god Tash are the same, referring to this combined being as "Tashlan".
Shift had one friend and neighbour who was a donkey called Puzzle. At least they both said they were friends, but from the way things went on you might have thought Puzzle was more like Shift's servant than his friend.
Dropped a Bridge on Him: Susan survives having not been on the train, but is written out of the story. The Pevensie children claim that she stopped believing in Narnia and started dismissing her adventures as childhood games. The effect is anticlimactic.
Dying Like Animals: Most of the characters are Sheep who are duped into surrendering to the Calormenes without a fight; Shift the Ape and Ginger the Cat are Snakes; Puzzle the Donkey is gullible enough that Shift convinces him to go along with his plans; and the dwarves go off on their own totally unjustified Civil War, before their ultimate fate of Flat Earth Atheist blindness to anything beautiful in their environment.
Getting Crap Past the Radar: In a conversation with talking Dogs, it is said that male pups that don't behave are often called "Boys." One mentions that female dogs are called "Girls" instead, and another dog tells him not to use that word because it's rude.
Subversion - Tirian and the crew head back to find Roonwit and the troops he was bringing from Cair Paravel only to find out from Farsight the eagle that Cair Paravel has been sacked by Calormen, and Roonwit is dead.
Played straight with the Calormenes. They call for help, and it comes! ("Mordor Calls for Help"?)
Hoist by His Own Petard: Shift brings the Calormenes into Narnia to help him rule it, they promptly reduce him to a figurehead. Ginger and the Tarkaan Rishda perpetuate the idea of "Tashlan", and are respectively made-unintelligent and taken to Hell by Tash.
Hollywood Tactics: Averted, most notably when Jill and Farsight — the only ranged combatants — are sent to flank the attacking Calormenes.
Honor Before Reason: Tirian and Jewel are so ashamed of killing the Calormene slavemasters in unfair combat that they voluntarily surrender their weapons and allow themselves to be captured. They were under the belief that Aslan had ordered the Calormenes to use the Talking Horses, so they felt it was necessary to be punished because they had deeply blasphemed.
“Do you think I care if Aslan dooms me to death?” said the King. “That would be nothing, nothing at all. Would it not be better to be dead than to have this horrible fear that Aslan has come and is not like the Aslan we have believed in and longed for? It is as if the sun rose one day and were a black sun.”
Hope Spot: The Talking Horses charging to the rescue, only to be shot down by the dwarves.
Kill 'em All: Played with. Since the final book deals with the afterlife, the character who gets effectively written out is the one who didn't die, nor was she on the train.
King in the Mountain: Father Time was once a great king, but sleeps underground (some of the characters saw him in The Silver Chair), to wake at the end of the world.
Laser-Guided Karma: Ginger the cat, who takes over from Shift, creates the idea of "Tashlan", and doesn't believe either Tash or Aslan are real. Tash is very much real, and he reverts Ginger to a witless beast.
My God, What Have I Done?: Tirian and Jewel after they kill two of the Calormene soldiers they saw murdering the dryads and overworking and whipping a Talking Horse.
Nostalgia Heaven: The end of the book. They find themselves in "The England within England, the real England", where "no good thing is destroyed".
Paper-Thin Disguise: Puzzle's disguise as Aslan is woefully bad. The only reason anybody falls for it is because it's dark when they see him, because he never says anything, and because it's been years since anybody saw a living lion.
Pre Asskicking One Liner: "This is my password. The light is dawning, the lie broken. Now guard thee, miscreant, for I am Tirian of Narnia."
Rail Enthusiast: Edmund is described as “the sort of person who knows about trains.”
Real Life Writes the Plot: The train crash is based on a real accident that happened in Britain in 1955. Both real and fictional accidents were caused by a train bound for Bristol taking a sharp curve through a station at excessive speed and derailing.
Recursive Reality: Mr. Tumnus touches on the true nature of Narnia as "an onion where the layers get bigger as you peel them away"
Sacrificial Lamb: The dryad who comes to warn the king that the Talking Trees of Lantern Waste are being cut down (killing the dryads who inhabit them) dies right in front of Tirian and co. to emphasize the brutality and horror of the situation to the reader.
Scout Out: Averted; Jill Pole is flat-out called a member of the Girl Guides and has various skills enhanced by her membership, namely tracking and archery.
Self-Inflicted Hell: The "Last Judgment" of Narnia is precisely this — Aslan says not a word; the creatures all come up to him, look him in the face, and either love him or reject him, essentially judging themselves and determining their own fate.
The dwarves in the stable are a more concrete example. They believe themselves to be in a dark stable, so they are.
Silly Rabbit, Cynicism Is for Losers!: The dwarves end up in Aslan's country with everybody else, but they're too cynical to believe it, and manage to delude themselves into believing they're still locked in a dark stable eating rotten food
Shut Up, Hannibal!: Tirian tries, early in the book, but he is cut short and silenced by Shift's followers.
Stupid Neutral: The Dwarves refuse to ally themselves with the Calormenes or with the heroes. Then they start shooting at either side to prevent either side from gaining the upper hand. The worst example is their passing the Moral Event Horizon by killing a whole herd of horses who were rushing to Tirian's aid, then jeering at him before invoking the Stupid Neutral idea behind their behaviour.
Take Our Word for It: Lewis ends the story by claiming that the previous adventures were book covers to the main stories that will follow. We'll never read about them, though. At least not in this world...
Worthy Opponent: Emeth, a noble Calormene soldier, is revealed to have been transported to Aslan's country after he volunteered to investigate the stable and see his god Tash for himself. The reason for this that the man honestly and truly believed in his god with a pure love and spirit, i.e. what Aslan would look for in a follower, and thus he counted him among his "flock" (this is definitely inspired by the "virtuous pagan" doctrine). By contrast, if the soldier had been a Narnian and had done cruel/evil things in Aslan's name, this would have given him over to Tash.
This was Emeth's own reaction on meeting High King Peter - "I know not whether you are a friend or an enemy, but I would be proud to have you for either. Has not one of the poets said that a noble friend is the best gift and a noble enemy the next best?"
Xanatos Speed Chess: Puzzle is captured and Tirian plans to reveal him to the Narnians as the false Aslan they've been following. By the time they return, however. Shift has already spread the word about a false Aslan and is using that to frame Tirian and his allies with the blame of deceiving everyone.
Shift's noted early on to be very good at this. When a Bolt of Divine Retribution strikes nearby after Shift and Puzzle think up the plan to pass himself off as Aslan, a quick-thinking Shift says he was about to say Aslan would send such a bolt of lightning to tell them he approves, only the bolt happened before he could get the words out. Later when a lamb protests allying with the Calormens because they worship the evil Tash, Shift just rebukes him and tells him Aslan and Tash are the same being.
Year Inside, Hour Outside: A reversal of the usual pattern of Narnian time running faster when Eustace and Jill arrive moments after Tirian's vision in Narnia, but days later in earth time.
Zerg Rush: The Calormenes eventually outmatch Tirian with sheer numbers.