I am here tonight to pledge
a hero's deed on knife's edge
his kingdom's name is a plant
find it in places moisture scant.
The castle on the verge to fall,
due to a flock of livings small.
It was left without powers,
as it had lost both its towers.
Firstly, the king assumed command
from his archbishop confidant.
He had to make the hard decision,
and act with so much irrision
as all the kingdom's fine people
were core struck by eerie creeple.
On agony's beginning moments,
the kingdom was approaching lowest.
The king's informant promptly tried
a safe exit to provide
but things were just too late, too grim
rendered the info, alas, limp.
The moment of truth came,
the frame of castle tame,
this was a huge success,
but things wer'n't out of distress.
People from foreign lands
reached out with stretching hands
and with their best they did strive
to lose, as few as they could, lives.
In the end they all survived,
goodness, joy, comfort thrived
only the castle was lost
but they could cope with that cost.
The king should be the first to praise.
But forget not all in this case:
The archbishop on the next place,
The informant who raced to place,
The woman knights who led the race,
The commoners who run with grace,
The out'ers who gave some space.
Now that I told you all the story,
I've still one tip for riddle's glory.
The king and his plant name bridges
a prime number with four digits.
Who is the king? What is his plant name?
Hint 1
The "kingdom's name" is not only the plant I ask you to find, it has also a 4-digit number at its end.