the sandy shore
chasing night away
Out to the ocean’s distant horizon
Night patiently lurks among the currents
waiting for the moon’s
cold glare to push
the sun back
The tetractys is a five-line poem with 20 total syllables, arranged like this: 1–2–3–4–10
So the first four lines together have ten syllables and the last line has ten syllables.
If you like longer poems, you can extend the tetractys:
and so one.