Declension table of ?mahāviṣṇu

Masculine	Singular	Dual	Plural
Nominative	mahāviṣṇuḥ	mahāviṣṇū	mahāviṣṇavaḥ
Vocative	mahāviṣṇo	mahāviṣṇū	mahāviṣṇavaḥ
Accusative	mahāviṣṇum	mahāviṣṇū	mahāviṣṇūn
Instrumental	mahāviṣṇunā	mahāviṣṇubhyām	mahāviṣṇubhiḥ
Dative	mahāviṣṇave	mahāviṣṇubhyām	mahāviṣṇubhyaḥ
Ablative	mahāviṣṇoḥ	mahāviṣṇubhyām	mahāviṣṇubhyaḥ
Genitive	mahāviṣṇoḥ	mahāviṣṇvoḥ	mahāviṣṇūnām
Locative	mahāviṣṇau	mahāviṣṇvoḥ	mahāviṣṇuṣu

Compound mahāviṣṇu -

Adverb -mahāviṣṇu