50 themes, one sentence each.
Freedom
When Thalia kneels before Artemis and takes her oath, she can all but feel the weight of the world drop off her shoulders, and for the first time in her life, she is free.
Bonds
It takes Zoë all of three hours with her new family to decide that bonds of blood are highly overrated.
Clouds
Even as the daughter of Atlas flees for her life, a tiny part of her registers her wonder at the fact that clouds don't always boil madly.
Moon
Romeo was an idiot, Thalia decides, for saying the moon was inconstant and disloyal; Artemis remarks idly that he did, however, make a very fine jackalope, and Thalia once again revises her knowledge of the classics.
Comfort
Thalia felt she stuck out like a sore thumb the first time she say down at Artemis' right hand, but then Cynthia squeezed her hand gently, and the new lieutenant realized that she was home.
Rain
Just because she's a daughter of Zeus and doesn't get rained on unless she wants to, Thalia grumbles under her breath while collecting firewood in a downpour, does not mean she wouldn't rather be inside.
Sky
Zoë always navigated using Ursa Major, Thalia recalls, but she can never look at the stars now without watching the newest constellation, so she learns how to use it as a map; she feels safer with Zoe guiding her, anyway.
Fear
She's faced countless monsters—she's been killed, for Zeus' sake—but somehow nothing was as scary as standing outside Cabin Eight that first night, and Thalia doubts she would ever have gone in if Artemis hadn't been at her side.
Socks
After a few weeks living with Ari McMurphy, Thalia gives up on ever being able to find matching socks; she just tries to stop them from being used as firestarter.
Name
The flower is beautiful but deadly; appropriate, so Zoë takes her name from it, because she can no longer introduce herself as "daughter of Atlas" even if she wanted to; and besides, what better name for a nymph of the sunset?
Potatoes
Demeter would be angry about the blatant abuse of such a useful legume…but it was winter and she was upset anyway, so Thalia saw no reason to interfere with Ari's impromptu game of Potato Hockey on Ice.
Light
Artemis had been her light on the darkest night of her life, and from the instant they met Zoë's loyalty never diminished; but as she died, the goddess found herself wishing that it had, just a little.
Happiness
The news reaches the Hunters quickly that Luke has somehow survived the fall, and Thalia knows she shouldn't be happy, but she is.
Enterprise
Thalia was reluctant enough to spend the day with Apollo; she would have refused outright if Artemis hadn't conveniently forgotten to mention he was a Trekkie.
Worry
Tori never lets Kim out of her sight, but the beautiful daughter of Aphrodite still reaches out anxiously from time to time, as if afraid her sister will disappear and leave her alone in the dark.
Trapped
With her legs crushed under the stupid statue, Thalia watches the only true friends she has left run off without her, and for the first time she realizes the world is already starting to leave her behind.
Telephone
They don't know where Ari got her smartphone and they're not about to ask; all they care about is that she has the best pizza place in the country on speed-dial.
Breathing
Thalia had never realized what fresh air really was until she took her first breath as a Hunter.
Jealousy
Even after two hundred years, it still causes a flare of pain and—she admits it—a bit of anger when Thalia realizes that no matter what she does, she will never be Zoë's equal, not to Artemis.
Promise
She never tells anyone but her goddess what they talked about in the cab of that crappy old pickup, but she promised Zoë that if anything happened to her she would take care of the Hunters, and that's what she plans to do.
Blood
At first Thalia harbored a vain hope that they could be saved, but when she fought her way to Tori and Kim's side and saw the blood, she realized they were already gone.
Confusion
When she realized Zoë wasn't going to make it, Thalia's world turned upside-down, because she realized she would miss her, and it didn't make any sense.
Tears
In the middle of the battle for Olympus, amid screams of pain and anguish, one girl sheds tears of pure joy, because for a terrible minute Cynthia thought Alene hadn't made it out of the tunnel before it collapsed.
Home
The others can think what they please; to Thalia, Camp Half-Blood is and has always been home.
Ice
Ari is shivering uncontrollably, dripping wet and huddled under a thick blanket next to the fire, but she's grinning like the maniac she is; because, sure, the ice wasn't as thick as they thought it was, but it had still been the best game of Potato Hockey ever.
Gravity
Phoebe is trying not to laugh as Thalia inches nervously across the bridge to Olympus; she isn't trying very hard, and the lieutenant glares and informs her coolly that it's not the drop that worries her, thank you very much; it's the huge splat at the bottom.
Chocolate
Olympian chocolate is not only heavenly—no pun intended—it's also safe to eat as much as you like; this, Thalia muses, is probably not a good thing, and she's grateful she burns so many calories.
Star
Every time she sees a shooting star, Zoë wishes for things to stay the same, and after a few millennia she begins to suspect that Zeus likes tormenting her.
Technology
Thalia loves the dignity and charm of Artemis' deer-drawn chariot; but one day Apollo's teasing makes the goddess angry enough to agree to a race, and Thalia discovers she loves the sleek silver Ferrari even more.
Waves
Thalia is less than amused when the waves at the beach are perfectly calm while she walks with Annabeth, but the minute the daughter of Athena is called away a huge breaker knocks the dark-haired daughter of Zeus off her feet.
Hair
Thalia had always planned to keep her hair short, but Kim was always the one to cut it; her eventual thick braid feels like a testament to her fallen sister.
Weakness
She tries to be strong when Artemis meets her halfway to the hall of the gods to tell her about Luke, but the goddess' eyes are too knowing, and she ends up sobbing into her shoulder.
Devotion
Thalia never understood the Hunters' blind loyalty until Artemis held a dying Zoë in her arms, and she realized it was because the devotion worked both ways.
Heaven
The Hunters flank Thalia defensively when they meet the campers in Manhattan, and even though she knows their protectiveness is unnecessary she's on top of the world knowing that they care.
Hell
Artemis takes pity on her and goes inside first, to explain things to the Hunters; but even so, the utter silence when Thalia walks in, silver lieutenant's band glittering almost indecently on her brow, makes her nauseas.
Loss
Ari was at least fifty years old, but in many ways she was still a child; she asked innocently after the battle where Angela was, and all present felt a pang in their hearts when they realized that she never really thought her best friend wouldn't come back.
Sun
She may be a Hunter, and he may be irritating and infuriating, but still…Apollo is hot.
Completion
Finally, Cynthia stands and holds out a hand, and Thalia takes it hesitantly; Cynthia hugs her and says, "Welcome to the family," and suddenly the daughter of Zeus wonders what she was worried about.
Pain
Thalia tries to wave Diana away from her injured leg, telling her that Sasha needs a lot more attention; but at the look on the healer's face she knows that the girl is beyond help.
Soft
Kim is asleep, leaning against a tree; Owen's head rests lightly in her lap, and Thalia smiles as she watches them, because not everything in nature is about fighting, and she sometimes has trouble remembering it.
Sickness
The Hunter's enchantment means that Ari doesn't get pneumonia, but Artemis shakes her head and says teasingly that one of these days she's going to let the girl fall ill; maybe it would teach her a lesson.
Death
When the Hunters finally straggle together again after the battle, they are far too few.
Hands
Becky learned a number of new curses from her siblings at Camp, and she wasn't above using them on the Hunters, or laughing when Ari yelped and whipped her hand out of Becky's knapsack, trying to shake off the enchanted mousetrap clamped onto her fingers.
Speed
Thalia didn't realize how fast she was running that first day, until she realized they were keeping pace easily with the wolves.
Smile
It took days after Zoë's death, but Ari finally smiled, and Thalia was glad; though she really wished it hadn't required an explosion.
Gift
Thalia finally tracks down her mother's collection of sports cars; she immediately turns and tosses Ari the keys to the Porsche, and for a moment she's afraid the little girl will actually die of happiness.
Flame
The car is totaled in a week, of course, but all the Hunters were impressed by the size of the fireball.
Melody
Zoë very rarely sang, because it reminded her of the Hespirides; but when Alene was cold and scared, she held her close and murmured a sweet lullaby, and Cynthia, out of respect for their privacy, pretended she hadn't seen.
Innocence
The Hunters were young and sweet-faced and soft-spoken, and it was always a unique pride to watch them take down sons of Ares twice their size.
Forever
Thalia often stargazed, watching Zoë's constellation, and would realize all over again that she had forever; sometimes, it was overwhelming, but more often she was glad she never had to leave.