riddle - Tell me a story!

I've seen a lot of prefix-infix-suffix/Riley riddles lately on the site and have decided to write one myself; however, those of you who know me understand it won't be quite as simple. I'll try to make it as elegant as possible!

The Story

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This is a story about Sarah the Brave; she is a Nordic princess who doesn't do too well with authority. Her parents always tell her what to do, and she just wants to live her life. She decides to undergo a mystical journey across the lands of Latima; her goal, to learn as much as possible about the countless villages between her home in Sepan and the castles of Horus. Does she understand the dangers that lurk around each corner? Or will the overwhelming facts of life destroy her?

Sarah sought a dragon, perched on its post; the dragon called out, what's desired the most.
The path which you seek, I'll give it one time; a word which would seem, is lost in my rhyme.
The prefix is former, found back in time; it's equal to the suffix, and infix in line.
Look to the past, but don't overthink; as soon as you have it, try not to blink.

The dragon stood tall, its wings spread wide; and with a huge leap, it took to the sky.

Sarah set out, a quest she'll complete; unknown to her, three more words she will seek.

Joined by an troll, who spoke of wonders untold; listen to his story, the second word will unfold.
Look up! Look up! The angry troll said. Pay me attention, or you'll end up dead.

A prefix of wonder, twenty one, in fact; it looks like a rainbow, flipped and turned black.
The suffix is simple, two letters you'll need; you'll find them on this rock, look, you can see.
Just like the prefix, the infix is capped; examine the sea, and find the humpback.

They rested over-night, by the dwindling fire; the troll was well rested, and Sarah inspired.

They continued their journey, it went on for days; they traveled until, the road split four ways.

A demon appeared, a sign of sure doom; he kindled a fire, rolling in plumes.

He summoned his wall, of broken letters; he pointed to the first, and said he is better.
A riddle I have, one just for you! Look at my face, I said one, not two.
The prefix and infix, the suffix the same; you'll need to think, to win my game.
These crossroads are mine, and I never lose; so pick just one letter, go on, go choose.

The situation looked bleak, yes dark indeed; but they weighed all the options, they found what you need.

The demon was mad, but he couldn't stay; he tipped his hat, another victim awaits.

Sarah went left, the troll went right; they both had a smile, their futures both bright.

The troll went home, he had much to do; and Sarah went North to a town called Tonu.

She walked to the gate, journey almost complete; a guardsman spoke up, he'd been watching for weeks.
Answer my riddle, and be on your way; all comers and goers, have a price they must pay.
The prefix comes first, but I'll bet it comes last; but wait, are you sure? Look, a dragon blew past!
The suffix is empty, exciting, empathic; this gate really gets, way too much traffic.
The infix refers, to both you and I; but only with am, apostrophe! Why?

Sarah heads home, and climbs in her bed; finally time for resting our heads.

Good luck to all of you!

Notes and Hints

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In the spirit of Riddled and Dismembered by Hugh Meyers; explain the title. You will have to solve the puzzle to do so, so keep in mind; the answer to the puzzle is:

• A phrase, not just one word.


• Quite common.

Hint #1: Sarah needed some hints along her journey, the first was given by a wanderer who referred to himself as the keeper.

The dragon has told you? Well, obviously not; past tense phrasing as food for thought.
The word which you seek, hidden remains; its prefix, suffix, and infix the same.
Once you grasp it, as time has foretold; you'll move forward, as soon as you're bold.

Answer

Final answer:

The path which you seek, I'll give it one time; a word which would seem, is lost in my rhyme.
The prefix is former, found back in time; it's equal to the suffix, and infix in line.
Look to the past, but don't overthink; as soon as you have it, try not to blink.

ONCE... the word lost in his rhyme is "once". It's lost because it means "one time", which he just said.
Prefix: "once" m-w.com defines former (definition 4) as "having been previously : onetime", and onetime is defined as (m-w.com definition 2) "occurring only once". I guess the whole word as a prefix is legal.
Suffix, infix: The suffix in "line" is E, and the infix in "line" is N, so this word has an equal suffix and infix as the suffix and infix in "line".

Look up! Look up! The angry troll said. Pay me attention, or you'll end up dead.
A prefix of wonder, twenty one, in fact; it looks like a rainbow, flipped and turned black.
The suffix is simple, two letters you'll need; you'll find them on this rock, look, you can see.
Just like the prefix, the infix is capped; examine the sea, and find the humpback.

UPON... The troll said "UP".
Prefix: U is the 21st letter in the alpabet, and a flipped, black rainbow would look like the letter U.
Suffix, two letters found "on this rock" is ON.
Infix: A letter P looks like the prefix (letter u) turned 90 degrees and capped. If you examine the sea (letter c), flip it horizontally and add a line on the left side, it also becomes the letter P. Letter P looks like there's a hump on its back.

A riddle I have, one just for you! Look at my face, I said one, not two.
The prefix and infix, the suffix the same; you'll need to think, to win my game.
These crossroads are mine, and I never lose; so pick just one letter, go on, go choose.

A... A is the first letter in the alphabet, and the word "one" is repeated.

Prefix, infix, suffix: The prefix and infix, suffix the same.

Answer my riddle, and be on your way; all comers and goers, have a price they must pay. The prefix comes first, but I'll bet it comes last; but wait, are you sure? Look, a dragon blew past! The suffix is empty, exciting, empathic; this gate really gets, way too much traffic. The infix refers, to both you and I; but only with am, apostrophe! Why?

TIME... Everyone's price to pay for anything, especially a weeks-long journey is time.
Prefix: the letter T comes last in the word first, and it also comes last in this line (the end of the word past).
Suffix: E (empty, exciting, empathetic all start with e)
Infix: IM is a word (only if you add an apostrophe) that you can say (I'm), and I can say it too (I'm). So it refers to both of us.

So in the response to the title "Tell me a story!", Sarah starts out with "Once Upon A Time"