Well, this effort does not meet any of the rules for this competition.

It started well but took on a life of its own. It is too long, and it's not an adventure, so I crave your indulgence for posting it:
The shortest day, the longest night,
'Midst forest trees a fire burned bright.
As moon on high lit up the trees
Red sparks danced skywards on the breeze.
In wearied comfort huddled there
Sat Bilbo, Gandalf, Beorn the bear.
'Neath starlit heaven’s ghostly light
They lay to rest through deepest night.
They talked of days just now passed by
Of goblins, trolls, and how, on high,
The eagles watched their toils below
And came to save them from their foe.
The suddenly there came the sound
Of swishing wings that wheeled around
Their glowing fire far below
Which lit their camp midst ice and snow.
Up leapt Beorn and Bilbo too,
Craning necks to get a view
What could it be up in the air
What creature gazed upon them there?
Beorn was first to spot the trail
Of fiery breath ‘gainst moon so pale;
From flaming mouth came forth that roar
That men so feared in days of yore.
Bilbo’s face creased in dismay
“A dragon! Run! We cannot stay
out here for such a beast to see -
into the forest we must flee!”
But as those whirring wings drew nigh
There came strange sounds from up on high
Of splintered branches, cries of woe,
And anguished pleas to those below:
“Help me strangers, give me aid!
Away from kin I boldly strayed
And now I cannot find my home
And I am scared and all alone.
I saw your fire and thought it might
Be my sweet mama, breathing light
As she came out to search for me -
But now I know it is not she.
I miss her so, where can she be?
And now I’m tangled in this tree
Please help to get me down from here
And help me find my kin so dear!”
And then to everyone’s surprise
Came tears of woe from dragon eyes;
The three below were moved to feel
True pity for his grief so real.
Now Gandalf stood and peered aloft
Then turned to Beorn and, speaking soft,
Said “You & I both know fine well
Where this young pup is sure to dwell.
I feel that I should give him aid
E’en though I know what path is laid
Before our feet, and where we’ll go,
To meet again, with him as foe.”
Beorn was silent; Bilbo too.
But deep inside the travellers knew
That they could not ignore the plight
Of one so young, on this dark night.
So even thought they knew that soon
‘Neath different stars and newer moon
This dragon pup would come of age
And in his wrath, would vent his rage
On them and maybe others too -
they knew exactly what to do;
So Bilbo climbed high in the tree
and set the hapless dragon free.
They dried his tears and in the light
Of moon and fire burning bright
They drew a map that showed the way
To guide him on at break of day.
And so their young guest took his leave
But midst their joy, all three did grieve;
For our friends knew that come the day
On distant mountains, far away
The dragon’s instincts would shine through
And friendship vows would not ring true.
And yet within their hearts that night
They knew that what they did was right.