Herculi
Herculi is a Latin form of hercules, meaning “Hercules, son of Jupiter and Alcmena; (hercle, mehercule) by Hercules!, indeed!”. It is the dative singular masculine noun.
Found 38 times in the Latin texts on Socratos.
Where it is used
Cicero, De Republica fr.6: Si fas endo plagas caelestum ascendere cuiquam est, Mi soli caeli maxima porta patet, Est vero, Africane; nam et Herculi eadem ista porta patuit.
Plautus, Epidicus 2.1.179: neque séxta aerumna acérbior Herculí, quam illa mihi obiéctast.
Plautus, Stichus 1.3.233: ut decumam partem Hérculi polluceam.
All forms of hercules (declension table)
Source: Socratos (socratos.org), a free reader for Ancient Greek and Latin. Grammar from the Perseus Treebank and Morpheus; dictionary entries from Lewis & Short, A Latin Dictionary (Perseus Digital Library, CC BY-SA). Counts are from the texts on Socratos.