Declension table of ?siddhaka

Neuter	Singular	Dual	Plural
Nominative	siddhakam	siddhake	siddhakāni
Vocative	siddhaka	siddhake	siddhakāni
Accusative	siddhakam	siddhake	siddhakāni
Instrumental	siddhakena	siddhakābhyām	siddhakaiḥ
Dative	siddhakāya	siddhakābhyām	siddhakebhyaḥ
Ablative	siddhakāt	siddhakābhyām	siddhakebhyaḥ
Genitive	siddhakasya	siddhakayoḥ	siddhakānām
Locative	siddhake	siddhakayoḥ	siddhakeṣu

Compound siddhaka -

Adverb -siddhakam -siddhakāt