Declension table of ?kṛṣṇavastra

Neuter	Singular	Dual	Plural
Nominative	kṛṣṇavastram	kṛṣṇavastre	kṛṣṇavastrāṇi
Vocative	kṛṣṇavastra	kṛṣṇavastre	kṛṣṇavastrāṇi
Accusative	kṛṣṇavastram	kṛṣṇavastre	kṛṣṇavastrāṇi
Instrumental	kṛṣṇavastreṇa	kṛṣṇavastrābhyām	kṛṣṇavastraiḥ
Dative	kṛṣṇavastrāya	kṛṣṇavastrābhyām	kṛṣṇavastrebhyaḥ
Ablative	kṛṣṇavastrāt	kṛṣṇavastrābhyām	kṛṣṇavastrebhyaḥ
Genitive	kṛṣṇavastrasya	kṛṣṇavastrayoḥ	kṛṣṇavastrāṇām
Locative	kṛṣṇavastre	kṛṣṇavastrayoḥ	kṛṣṇavastreṣu

Compound kṛṣṇavastra -

Adverb -kṛṣṇavastram -kṛṣṇavastrāt