Declension table of ?śvastya

Neuter	Singular	Dual	Plural
Nominative	śvastyam	śvastye	śvastyāni
Vocative	śvastya	śvastye	śvastyāni
Accusative	śvastyam	śvastye	śvastyāni
Instrumental	śvastyena	śvastyābhyām	śvastyaiḥ
Dative	śvastyāya	śvastyābhyām	śvastyebhyaḥ
Ablative	śvastyāt	śvastyābhyām	śvastyebhyaḥ
Genitive	śvastyasya	śvastyayoḥ	śvastyānām
Locative	śvastye	śvastyayoḥ	śvastyeṣu

Compound śvastya -

Adverb -śvastyam -śvastyāt