Declension table of ?mantrakārya

Neuter	Singular	Dual	Plural
Nominative	mantrakāryam	mantrakārye	mantrakāryāṇi
Vocative	mantrakārya	mantrakārye	mantrakāryāṇi
Accusative	mantrakāryam	mantrakārye	mantrakāryāṇi
Instrumental	mantrakāryeṇa	mantrakāryābhyām	mantrakāryaiḥ
Dative	mantrakāryāya	mantrakāryābhyām	mantrakāryebhyaḥ
Ablative	mantrakāryāt	mantrakāryābhyām	mantrakāryebhyaḥ
Genitive	mantrakāryasya	mantrakāryayoḥ	mantrakāryāṇām
Locative	mantrakārye	mantrakāryayoḥ	mantrakāryeṣu

Compound mantrakārya -

Adverb -mantrakāryam -mantrakāryāt