Declension table of ?tāntra

Masculine	Singular	Dual	Plural
Nominative	tāntraḥ	tāntrau	tāntrāḥ
Vocative	tāntra	tāntrau	tāntrāḥ
Accusative	tāntram	tāntrau	tāntrān
Instrumental	tāntreṇa	tāntrābhyām	tāntraiḥ
Dative	tāntrāya	tāntrābhyām	tāntrebhyaḥ
Ablative	tāntrāt	tāntrābhyām	tāntrebhyaḥ
Genitive	tāntrasya	tāntrayoḥ	tāntrāṇām
Locative	tāntre	tāntrayoḥ	tāntreṣu

Compound tāntra -

Adverb -tāntram -tāntrāt