Declension table of ?siddhakārya

Masculine	Singular	Dual	Plural
Nominative	siddhakāryaḥ	siddhakāryau	siddhakāryāḥ
Vocative	siddhakārya	siddhakāryau	siddhakāryāḥ
Accusative	siddhakāryam	siddhakāryau	siddhakāryān
Instrumental	siddhakāryeṇa	siddhakāryābhyām	siddhakāryaiḥ siddhakāryebhiḥ
Dative	siddhakāryāya	siddhakāryābhyām	siddhakāryebhyaḥ
Ablative	siddhakāryāt	siddhakāryābhyām	siddhakāryebhyaḥ
Genitive	siddhakāryasya	siddhakāryayoḥ	siddhakāryāṇām
Locative	siddhakārye	siddhakāryayoḥ	siddhakāryeṣu

Compound siddhakārya -

Adverb -siddhakāryam -siddhakāryāt