Declension table of ?mantrasādhyatva

Neuter	Singular	Dual	Plural
Nominative	mantrasādhyatvam	mantrasādhyatve	mantrasādhyatvāni
Vocative	mantrasādhyatva	mantrasādhyatve	mantrasādhyatvāni
Accusative	mantrasādhyatvam	mantrasādhyatve	mantrasādhyatvāni
Instrumental	mantrasādhyatvena	mantrasādhyatvābhyām	mantrasādhyatvaiḥ
Dative	mantrasādhyatvāya	mantrasādhyatvābhyām	mantrasādhyatvebhyaḥ
Ablative	mantrasādhyatvāt	mantrasādhyatvābhyām	mantrasādhyatvebhyaḥ
Genitive	mantrasādhyatvasya	mantrasādhyatvayoḥ	mantrasādhyatvānām
Locative	mantrasādhyatve	mantrasādhyatvayoḥ	mantrasādhyatveṣu

Compound mantrasādhyatva -

Adverb -mantrasādhyatvam -mantrasādhyatvāt