Declension table of ?pastya

Neuter	Singular	Dual	Plural
Nominative	pastyam	pastye	pastyāni
Vocative	pastya	pastye	pastyāni
Accusative	pastyam	pastye	pastyāni
Instrumental	pastyena	pastyābhyām	pastyaiḥ
Dative	pastyāya	pastyābhyām	pastyebhyaḥ
Ablative	pastyāt	pastyābhyām	pastyebhyaḥ
Genitive	pastyasya	pastyayoḥ	pastyānām
Locative	pastye	pastyayoḥ	pastyeṣu

Compound pastya -

Adverb -pastyam -pastyāt