Declension table of ?kṛṣṇya

Masculine	Singular	Dual	Plural
Nominative	kṛṣṇyaḥ	kṛṣṇyau	kṛṣṇyāḥ
Vocative	kṛṣṇya	kṛṣṇyau	kṛṣṇyāḥ
Accusative	kṛṣṇyam	kṛṣṇyau	kṛṣṇyān
Instrumental	kṛṣṇyena	kṛṣṇyābhyām	kṛṣṇyaiḥ kṛṣṇyebhiḥ
Dative	kṛṣṇyāya	kṛṣṇyābhyām	kṛṣṇyebhyaḥ
Ablative	kṛṣṇyāt	kṛṣṇyābhyām	kṛṣṇyebhyaḥ
Genitive	kṛṣṇyasya	kṛṣṇyayoḥ	kṛṣṇyānām
Locative	kṛṣṇye	kṛṣṇyayoḥ	kṛṣṇyeṣu

Compound kṛṣṇya -

Adverb -kṛṣṇyam -kṛṣṇyāt