योगवासिष्ठः yogavāsiṣṭhaḥ - book-7, chapter-71, verse-44

सरसेन विभोर्नाशैर्विशङ्कितमहानलाः ।
मिलच्छिखरिमालाग्रजलमातङ्गयोधिनः ॥ ४४ ॥

sarasena vibhornāśairviśaṅkitamahānalāḥ ,
milacchikharimālāgrajalamātaṅgayodhinaḥ 44

44. sarasena vibhoḥ nāśaiḥ viśaṅkitamahānalāḥ
milacchikharimālāgrajalamātaṅgayodhinaḥ

44. vibhoḥ nāśaiḥ viśaṅkitamahānalāḥ sarasena
milacchikharimālāgrajalamātaṅgayodhinaḥ

44. With great intensity, they are like vast, dreaded fires, resulting from the destructions wrought by the mighty one; they battle like water elephants (powerful water currents) at the peaks of converging mountain ranges.

Words meanings summery:

• सरसेन (sarasena) - with great intensity (intensely, passionately, with a roar, with enthusiasm)

• विभोः (vibhoḥ) - of the mighty one (of the omnipresent, of the Lord, of the mighty one, of the ruler)

• नाशैः (nāśaiḥ) - by destructions (by destructions, by losses, by ruins)

• विशङ्कितमहानलाः (viśaṅkitamahānalāḥ) - vast, dreaded fires (great fires that are dreaded, dreaded vast flames)

• मिलच्छिखरिमालाग्रजलमातङ्गयोधिनः (milacchikharimālāgrajalamātaṅgayodhinaḥ) - battling like water-elephants (powerful water currents) at the peaks of converging mountain ranges (fighters like water-elephants at the peaks of joining mountain ranges)

Words meanings and morphology

सरसेन (sarasena) - with great intensity (intensely, passionately, with a roar, with enthusiasm)

(adjective)

Instrumental, neuter, singular of sarasa

sarasa - full of juice, juicy, delicious, passionate, emotional, charming, vigorous, with sound/noise

From saras (juice, essence) + -a. Can also be related to saras (sound/noise).

Note: Used adverbially.

विभोः (vibhoḥ) - of the mighty one (of the omnipresent, of the Lord, of the mighty one, of the ruler)

(noun)

Genitive, masculine, singular of vibhu

vibhu - omnipresent, mighty, powerful, lord, ruler, controller

From vi-bhū (to be pervasive).

Root: bhū (class 1)

नाशैः (nāśaiḥ) - by destructions (by destructions, by losses, by ruins)

(noun)

Instrumental, masculine, plural of nāśa

nāśa - destruction, loss, ruin, disappearance

From root naś (to perish).

Root: naś (class 4)

विशङ्कितमहानलाः (viśaṅkitamahānalāḥ) - vast, dreaded fires (great fires that are dreaded, dreaded vast flames)

(noun)

Nominative, masculine, plural of viśaṅkitamahānala

viśaṅkitamahānala - great fire that is dreaded

Compound type : karmadhāraya (viśaṅkita+mahānala)

• viśaṅkita – feared, dreaded, apprehensive, suspicious
  adjective (masculine/feminine/neuter)
  Past Passive Participle
  Derived from root śaṅk with upasarga vi-
  Prefix: vi
  Root: śaṅk (class 1)
• mahānala – great fire, vast flame
  noun (masculine)

Note: This entire compound acts as the subject/description.

मिलच्छिखरिमालाग्रजलमातङ्गयोधिनः (milacchikharimālāgrajalamātaṅgayodhinaḥ) - battling like water-elephants (powerful water currents) at the peaks of converging mountain ranges (fighters like water-elephants at the peaks of joining mountain ranges)

(noun)

Nominative, masculine, plural of milacchikharimālāgrajalamātaṅgayodhin

milacchikharimālāgrajalamātaṅgayodhin - one who fights like water-elephants (clouds/powerful currents) on the tops of meeting mountain ranges

Compound type : karmadhāraya (milat+śikharimālā+agra+jalamātaṅga+yodhin)

• milat – meeting, joining, assembling
  adjective (masculine/feminine/neuter)
  Present Active Participle
  Derived from root mil
  Root: mil (class 6)
• śikharimālā – mountain range, garland of peaks
  noun (feminine)
• agra – top, summit, front, tip
  noun (neuter)
• jalamātaṅga – water elephant (referring to clouds or powerful water currents)
  noun (masculine)
• yodhin – fighter, warrior, one who battles
  noun (masculine)
  From root yudh
  Root: yudh (class 4)

Note: This compound functions as a predicate adjective or noun describing the subject (implicit).