Boojum.
Because its bad when the Snark that you are hunting, e.g. a newbie, turns out to be a Boojum, e.g. a skilled flyer.
The warning:
'But oh, beamish nephew, beware of the day, If your Snark be a Boojum! For then You will softly and suddenly vanish away, And never be met with again!'
The ending:
'For The Snark WAS A Boojum, You See!'
This from Lewis Carrol.
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We few, we happy few, we band of brothers;
For he to-day that sheds his blood with me
Shall be my brother
Sisu
-Karnak